Phase tracking reference signaling for a wireless communication network

ABSTRACT

There is disclosed a method of operating a receiving radio node in a wireless communication network. The method includes receiving signaling based on evaluating Phase Tracking Reference Signaling, PTRS, associated to the signaling, wherein evaluating is based on assuming a power level of PTRS relative to associated data signaling based on the number or PTRS ports and/or transmission sources for the signaling indicated to the receiving radio node. The disclosure also pertains to related devices and methods.

TECHNICAL FIELD

This disclosure pertains to wireless communication technology, inparticular for high frequencies.

BACKGROUND

For future wireless communication systems, use of higher frequencies isconsidered, which allows large bandwidths to be used for communication.However, use of such higher frequencies brings new problems, for exampleregarding physical properties and timing. Ubiquitous or almostubiquitous use of beamforming and/or the use of multiple TRPs havingsimultaneous communication links with one wireless device, with oftencomparatively small beams, may provide additional complications thatneed to be addressed.

SUMMARY

It is an object of this disclosure to provide improved approaches ofhandling wireless communication, in particular regarding referencesignaling. The approaches described are particularly suitable formillimeter wave communication, in particular for radio carrierfrequencies around and/or above 52.6 GHz, which may be considered highradio frequencies (high frequency) and/or millimeter waves. The carrierfrequency/ies may be between 52.6 and 140 GHz, e.g. with a lower borderbetween 52.6, 55, 60, 71 GHz and/or a higher border between 71, 72, 90,114, 140 GHz or higher, in particular between 55 and 90 GHz, or between60 and 72 GHz; however, higher frequencies may be considered, inparticular frequency of 71GHz or 72GHz or above, and/or 100 GHz orabove, and/or 140 GHz or above. The carrier frequency may in particularrefer to a center frequency or maximum frequency of the carrier. Theradio nodes and/or network described herein may operate in wideband,e.g. with a carrier bandwidth of 1 GHz or more, or 2 GHz or more, oreven larger, e.g. up to 8 GHz; the scheduled or allocated bandwidth maybe the carrier bandwidth, or be smaller, e.g. depending on channeland/or procedure. In some cases, operation may be based on an OFDMwaveform or a SC-FDM (also referred to as DFT-s-waveform), for examplefor downlink and/or uplink, in particular a FDF-SC-FDM-based waveform.However, operation based on a single carrier waveform, e.g. SC-FDE(which may be pulse-shaped or Frequency Domain Filtered, e.g. based onmodulation scheme and/or MCS), may be considered for downlink and/oruplink. In general, different waveforms may be used for differentcommunication directions. Communicating using or utilising a carrierand/or beam may correspond to operating using or utilising the carrierand/or beam, and/or may comprise transmitting on the carrier and/or beamand/or receiving on the carrier and/or beam. Operation may be based onand/or associated to a numerology, which may indicate a subcarrierspacing and/or duration of an allocation unit and/or an equivalentthereof, e.g., in comparison to an OFDM based system. A subcarrierspacing or equivalent frequency interval may for example correspond to960 kHZ, or 1920 kHz, e.g. representing the bandwidth of a subcarrier orequivalent.

The approaches are particularly advantageously implemented in a future6^(th) Generation (6 G) telecommunication network or 6 G radio accesstechnology or network (RAT/RAN), in particular according to 3GPP (3^(rd)Generation Partnership Project, a standardisation organization). Asuitable RAN may in particular be a RAN according to NR, for examplerelease 17 or later, or LTE Evolution. However, the approaches may alsobe used with other RAT, for example future 5.5G systems or IEEE basedsystems. It may be considered that the RAN and/or a radio node isoperating in an unlicensed frequency band (or carrier or part thereof,also referred to as license-exempt) and/or based on a LBT or channelassessment procedure to access (for transmission) the frequency band (orcarrier or part thereof), for example in a License Assisted Access (LAA)operation mode and/or in the context of NR-U (NR unlicensed).

There is disclosed a method of operating a receiving radio node in awireless communication network. The method comprises receiving signalingbased on evaluating Phase Tracking Reference Signaling, PTRS, associatedto the signaling. Evaluating is based on assuming a power level of PTRSrelative to associated data signaling based on the number or PTRS portsand/or transmission sources for the signaling indicated to the receivingradio node.

A receiving radio node for a wireless communication network isdescribed. The receiving radio node is adapted for receiving signalingbased on evaluating Phase

Tracking Reference Signaling, PTRS, associated to the signaling.Evaluating is based on assuming a power level of PTRS relative toassociated data signaling based on the number or PTRS ports and/ortransmission sources for the signaling indicated to the receiving radionode.

There is also proposed a method of operating a transmitting radio nodein a wireless communication network. The method comprises transmittingsignaling comprising Phase Tracking Reference Signaling, PTRS, whereinthe relative power level of the PTRS to associated data signaling of thesignaling is based on the number of PTRS ports and/or transmissionsources used for transmitting the signaling.

A transmitting radio node for a wireless communication network isconsidered. The transmitting radio node is adapted for transmittingsignaling comprising Phase Tracking Reference Signaling, PTRS, whereinthe relative power level of the PTRS to associated data signaling of thesignaling is based on the number of PTRS ports and/or transmissionsources used for transmitting the signaling.

Receiving signaling based on evaluating PTRS associated to the signalingmay comprise and/or be based on phase noise estimation and/or correctionfor common phase error and/or inter carrier interference (CPE and/orICI) based on the PTRS, which may consider relative power level betweenthe PTRS and the data signaling it is associated to. The data signalingmay in particular be PDSCH signaling. In some variants, instead of datasignaling, control signaling may be associated to the PTRS and/orincluded in the signaling. Data signaling may in general comprise firstdata signaling and/or second data signaling, which may have the same ordifferent number of layers, e.g. associated to different TRPs and/ortransmission sources. Control signaling may comprise first controlsignaling and/or second control signaling, which may be associated todifferent TRPs and/or transmission sources, e.g. as PDCCH transmitted onmultiple layers. For different (relative) power levels, the evaluationmay operate differently. In general, PTRS and associated data signalingor control signaling may be transmitted at different power levels;however, the power level may also be the same. The relative power levelmay be corresponding.

It may be considered that the signaling may comprise first signaling andsecond signaling, which may be associated to different TRPs ortransmission sources. In general, depending on the number of TPRs and/ortransmission sources and/or PTRS ports, the relative power level of PTRsand associated data or control signaling (e.g., between first PTRS andfirst data or control signaling; and/or between second PTRS and seconddata or control signaling) may be different.

It may be considered that the relative power level corresponds to atransmission power level. This level may be well-defined, whereas areception power level may be strongly dependent on pathloss, which maybe different for different signals.

In some variants, the signaling may comprise first signaling and secondsignaling, wherein the first signaling comprises first Phase TrackingReference Signaling, PT-RS, on a first set of subcarriers, and thesecond signaling comprises second PT-RS on a second set of subcarriers,wherein the first set of subcarriers is non-overlapping with the secondset of subcarriers. This allows limiting interference for the PTRS.

It may be considered that first signaling of the signaling may be mutedon a second set of subcarriers associated to second PTRS of secondsignaling of the signaling, and/or second signaling of the signaling maybe muted on a first set of subcarriers associated to first PTRS of firstsignaling of the signaling. The muted signaling may be data signaling orcontrol signaling, or reference signaling. Thus, the transmitter avoidsintroducing interference on the PTRS.

In general, the relative power level may be dependent on one or moreModulation and Coding Schemes associated to the signaling. Inparticular, different MCS may be associated to first signaling andsecond signaling. The MCS may pertain to transmission of data signalingin particular, and/or may be scheduled with multiple DCI, e.g. a firstDCI scheduling the first signaling and a second DCI scheduling secondsignaling, or in some cases on DCI scheduling different MCS fordifferent component (e.g., first and second) signalings of thesignaling. Thus, large flexibility may be provided, e.g. for linkadaptation.

It may be considered that the relative power level may be in conformancewith and/or according to, a table. The table may index the relativepower level based on one or more parameters, e.g. number of PTRS and/orlayers and/or MCS and/or type of scheduling; different tables may beassociated to different of such parameters. A table may pertain to afirst signaling of the signaling, and/or to first and second signalingof the signaling.

In general, the relative power level may be indicated by, and/or basedon, or on reference to Energy Per Resource Element, EPRE. It should benoted that in general, a relative power level may be associated to atransmission time of the signaling, e.g. covering one or more allocationunits or symbols. The relative power level may be in units of dBm.

Alternatively, or additionally, the method of operating a receivingradio node in a wireless communication network may comprise receivingfirst signaling and second signaling, wherein the first signaling maycomprise first Phase Tracking Reference Signaling, PT-RS, on a first setof subcarriers, and the second signaling may comprise second PT-RS on asecond set of subcarriers. The first set of subcarriers may benon-overlapping with the second set of subcarriers.

Alternatively, or additionally, the receiving radio node for a wirelesscommunication network may be adapted for receiving first signaling andsecond signaling. The first signaling comprises first Phase TrackingReference Signaling, PT-RS, on a first set of subcarriers, and thesecond signaling comprises second PT-RS on a second set of subcarriers,wherein the first set of subcarriers may be non-overlapping with thesecond set of subcarriers.

Alternatively, or additionally, the method of operating a transmittingradio node in a wireless communication network may comprise transmittingfirst signaling and second signaling, wherein the first signaling maycomprise first Phase Tracking Reference Signaling, PT-RS, on a first setof subcarriers, and the second signaling may comprise second PT-RS on asecond set of subcarriers. The first set of subcarriers may benon-overlapping with the second set of subcarriers.

Alternatively, or additionally, the transmitting radio node for awireless communication network may be adapted for transmitting firstsignaling and second signaling, wherein the first signaling may comprisefirst Phase Tracking Reference Signaling, PT-RS, on a first set ofsubcarriers, and the second signaling may comprise second PT-RS on asecond set of subcarriers. The first set of subcarriers may benon-overlapping with the second set of subcarriers.

In general, a set of subcarriers may comprise a plurality ofsubcarriers, which may be distributed over a frequency range associatedto, and/or allocated for data signaling to which the PTRS may beassociated. The frequency ranges for the first signaling and secondsignaling may overlap and/or be identical.

It may be considered that the first signaling is muted on the second setof subcarriers, and/or the second signaling is muted on the first set ofsubcarriers. The muting may be indicated to the receiving radio node,e.g. with control signaling, and/or may be configured or configurable,or predefined. For example, it may be configured via a CSI-RSconfiguration indicating subcarriers to be ZP-CSI-RS elements (e.g.,with RRC signaling), e.g. if the signaling is downlink signaling.

In some variants, the first set of subcarriers may be located indifferent Physical Resource Blocks than the second set of subcarriers.Each set may comprise subcarriers associated to and/or mapped to and/orlocated in different PRBs.

In general, the first set of subcarriers may be offset from the secondset of subcarriers by one or more subcarriers. In particular, asubcarrier of the first set located in the same PRB as a subcarrier ofthe second set may be shifted or offset in frequency domain by the oneor more subcarriers (which may be empty or carry signaling, e.g. datasignaling).

It may be considered that the first set of subcarriers may be clustered,and/or the second set of subcarriers may be clustered. Multiple clustersmay be distributed over the allocated frequency range (for the firstsignaling and/or second signaling). Clusters of subcarriers of the firstset may be shifted or non-neighbouring in frequency domain from clustersof subcarriers of the second set.

It may be considered that the first set of subcarriers and the secondset of subcarriers are interlaced or interleaved, e.g. clusters ofsubcarriers may be interlaced or interleaved.

The first PTRS may be represented by a signaling sequence or sequence ofmodulation symbols, which may be cyclic, e.g. within a cluster. Thesecond PTRS may be represented by a signaling sequence or sequence ofmodulation symbols, which may be cyclic, e.g. within a cluster. Thesequences of the first PTRS may be shifted relative to the sequence ofthe second PTRS, e.g. based on a code or cyclic shift.

The receiving radio node may comprise radio circuitry, in particularreceiver circuitry or circuitries for receiving the first signalingand/or second signaling and/or processing circuitry for processing such.Radio circuitry and/or processing circuitry may be adapted forestimating the phase noise and/or filtering (e.g., de-ICI filtering)and/or demodulating and/or decoding the signaling. Receiving maycomprise demodulating and/or decoding the first signaling and/or thesecond signaling, in particular data signaling and/or communicationsignaling and/or control signaling associated thereto and/or comprisedtherein, e.g. based on the estimated phase noise. Processing signalingmay comprise demodulating, and/or decoding, and/or estimating phasenoise, and/or performing an ICI correction, and/or filtering of or forsignaling. The receiving radio node may be implemented as a wirelessdevice or terminal or UE or feedback radio node; however, in somevariants it may be implemented as network node or signaling radio node.

The transmitting radio node may comprise radio circuitry, in particulartransmitter circuitry or circuitries for transmitting the firstsignaling and/or second signaling and/or processing circuitry forprocessing such. Radio circuitry and/or processing circuitry may beadapted for modulating and/or coding the first signaling and/or thesecond signaling, in particular data signaling and/or communicationsignaling and/or control signaling associated thereto and/or comprisedtherein, and/or mapping PTRS and/or data or control signaling associatedthereto to frequency resources. Processing signaling may comprisemodulating, and/or coding, and/or mapping the signaling and/or PTRS. Thetransmitting radio node may be implemented as a network node or basestation or signaling radio node; however, in some variants it may beimplemented as wireless device or terminal or UE or feedback radio node.

The first signaling and the second signaling may each comprise datasignaling and/or control signaling and/or communication signaling. Thefirst PTRS may be associated to the data signaling and/or controlsignaling and/or communication signaling of the first signaling. Thesecond PTRS may be associated to the data signaling and/or controlsignaling and/or communication signaling of the second signaling. Thepayload of the first and second signaling may be the same in somevariants, e.g. when scheduled with a single DCI, and/or may beassociated to the same channel or channel type, e.g. data channel orcontrol channel, e.g. PDSCH or PUSCH or PUCCH or PDCCH. There may beconsidered examples in which the payloads may be different. The payloadmay correspond to user data and/or control information bits. A first setof subcarriers may be considered non-overlapping with a second set ofsubcarriers if no subcarrier of the first set is also a member of thesecond set (and/or vice versa). The first set and the second set may bedistributed in clusters, such that multiple subcarriers of the first set(e.g., N1) and multiple subcarriers of the second set (e.g., N2) mayform a continuous and/or neighboring set of subcarriers, e.g. coveringN1+N2 subcarriers. N1 and N2 may be equal, or different in some cases.There may be multiple sets forming multiple clusters in frequencydomain. The first PT-RS and the second PT-RS may be transmitted and/orreceived simultaneously, e.g. withing a cyclic prefix length, and/or onthe same symbol time interval or allocation unit. The phase noise mayrepresent the phase noise of the first signaling, which may have acomponent due to the second signaling. The first signaling and secondsignaling may be scheduled (e.g., dynamically) with the same DCI (e.g.,a single DCI), or with different Das (e.g., multiple DCIs).

In general, the first signaling may be transmitted by a differenttransmission source or TRP than the second signaling. For example, thefirst signaling may be transmitted by a first TRP and the secondsignaling may be transmitted by a second TRP. Alternatively, oradditionally, the first signaling and/or first PTRS may be associated toa first antenna port or DMRS port or PTRS port, and the second signalingand/or second PTRS may be associated to a second, different, antennaport or DMRS port or PTRS port. Signaling associated to different portsmay be orthogonalised, e.g. by cyclic shift and/or code and/or frequencydomain distribution. Different TRPs or transmission sources may beassociated to and/or controlled by the same transmitting radio node,e.g. the same base station or network node or wireless device.

It may be considered that the first signaling is muted on the second setof subcarriers (carrying PTRS of the second signaling), and/or thesecond signaling is muted on the first set of subcarriers (carrying PTRSof the first signaling). In particular, the first signaling may comprisezero power transmission on the second set and/or may not transmit amodulation symbol or signal on subcarriers of the second set, and/orvice versa for the second signaling. Thus, the PT-RS of one signalingare subject to limited interference.

Transmitting signaling may comprise transmitting first and secondsignaling (or more reference signalings). Different signalings may betransmitted on different TPs or separate antennas and/or antenna portsand/or have different polarization and/or be on the same beam ordifferent beams (e.g., showing Quasi-CoLocation QCL in one or moreparameters) and/or may be shifted relative to each other. Communicationsignaling and reference signaling may be associated to different portsand/or antenna elements and/or beams and/or transmission or beam orsignaling characteristics. Receiving reference signaling like PTRS orDMRS may comprise measuring, and/or perform measurements on, thereference signaling and/or providing a measurement report based on thereference signaling (e.g., the measurements).

It may be considered that the first signaling and second signaling maybe synchronised to each other. In particular, they may start and/or endat the same times, and/or have allocation units with coinciding bordersin time domain. A transmission time interval may correspond to a numberCT of allocation units in time domain; both first and second signalingmay extend over the CT allocation units. Simultaneous transmission ofthe first and second signaling may be effected. The synchronisation maybe provided by the transmission radio node, which may e.g. transmit thesignalings accordingly. The first and second allocation units may beconsidered to represent the same time domain intervals; as they may beconsidered to be attached or associated to different transmissions ortransmission structures, they may be considered separate. However, insome perspectives (e.g., considering synchronisation), the firstallocation units may be considered the same as the second allocationunits. In some variants, the first and/or second allocation units mayrepresent and/or contain and/or correspond to only one allocation unit,e.g. for a short signaling transmission, or two or less, or four or lessallocation units. Each of the first and/or second signaling maycorrespond to one transmission or occurrence, or to several, e.g.consecutive in time domain and/or frequency domain (e.g., mapped suchthat parts of two occurrences are mapped to the same allocation unit,but different subcarriers or PRBs).

In general, second PTRS or DMRS may overlap and/or coincide in time withfirst PTRS or DMRS. The first and second PTRS and/or DMRS associated tothe first and/or second signaling and/or the first and second signalingmay be transmitted on the same carrier and/or bandwidth part and/or withoverlapping frequency domain extension, e.g. according to scheduling.The first and second signaling may be scheduled with one DCI orscheduling assignment, or with multiple DCIs.

It may be considered that second reference signaling may be shiftedrelative to the first reference signaling by having a different mappingof modulation symbols to resources. Resources may in particular be timeand/or frequency resources, in particular subcarriers (e.g., in the sametime interval corresponding to an allocation unit) and/or resourceelements and/or resource blocks or other resource structure/s. Thisfacilitates simple processing, e.g. to achieve suitablepseudo-orthogonality.

In general, second reference signaling may have a different transmissionsource than first reference signaling.

In general, the wireless device and/or network node may operate in,and/or the communication and/or signaling may be in, TDD operation. Itshould be noted that the transmission of signaling from transmissionsources may be synchronised and simultaneous; a shift in time may occurdue to different propagation times, e.g. due to different beams and/orsource locations.

Reference signaling like PTRS (Phase Tracking RS) or DMRS may beconsidered associated to a data block if it allows and/or is intended toallow demodulation and/or correction for phase noise or phase errors ofthe signaling associated to the data block, e.g. based on processingand/or filtering based on received reference signaling.

A wireless device and/or feedback radio node (a wireless device may beconsidered an example for a feedback radio node), may in generalcomprise, and/or be adapted to utilise, processing circuitry and/orradio circuitry, in particular a transmitter and/or transceiver and/oreceiver, to process (e.g., trigger and/or schedule) and/or transmitand/or receive signaling like data signaling and/or control signalingand/or reference signaling, in particular first signaling and secondsignaling. A wireless device or feedback radio node may be implementedas terminal or UE; in some cases, it may however be implemented asnetwork node, in particular a base station or relay node or IAB node, inparticular to provide MT (Mobile Termination) functionality for such. Ingeneral, a wireless device of feedback radio node may comprise and/or beadapted for transmission diversity, and/or may be connected orconnectable to, and/or comprise, antenna circuitry, and/or two or moreindependently operable or controllable antenna arrays or arrangements,and/or transmitter circuitries and/or antenna circuitries, and/or may beadapted to use (e.g., simultaneously) a plurality of antenna ports(e.g., for transmitting first signaling and second signaling), e.g.controlling transmission using the antenna array/s, and/or to utiliseand/or operate and/or control two or more transmission sources, to whichit may be connected or connectable, or which it may comprise. Thetransmitting radio node may comprise multiple components and/ortransmitters and/or transmission sources and/or TRPs (and/or beconnected or connectable thereto) and/or be adapted to controltransmission from such. Any combination of units and/or devices able tocontrol transmission on an air interface and/or in radio as describedherein may be considered a transmitting radio node.

A signaling radio node and/or network node (a network node may beconsidered an example of a signaling radio node) may comprise, and/or beadapted to utilise, processing circuitry and/or radio circuitry, inparticular a receiver and/or transmitter and/or transceiver, to transmitand/or to process and/or receive (e.g. receive and/or demodulate and/ordecode and/or perform blind detection and/or schedule or trigger) datasignaling and/or control signaling and/or reference signaling, inparticular first signaling and second signaling. Receiving may comprisescanning a frequency range (e.g., a carrier) for reference signalingand/or control signaling, e.g. at specific (e.g., predefined and/orconfigured) locations in time/frequency domain, which may be dependenton the carrier and/or system bandwidth. Such location/s may correspondto one or more location or resource allocations configured or indicatedor scheduled or allocated to a feedback radio node, e.g. scheduleddynamically, or configured, e.g. with DCI and/or RRC signaling, e.g. fortransmission on resources allocated for data signaling. In some cases, asignaling radio node may be a network node or base station or TRP, ormay be an IAB node or relay node, e.g. providing control levelfunctionality for such, e.g. DU and/or CU functionality. In some cases,e.g. sidelink scenarios, a signaling radio node may be implemented as awireless device or terminal or UE. A signaling radio node or networknode may comprise one or more independently operable or controllablereceiving circuitries and/or antenna circuitries and/or may be adaptedto utilise and/or operate to receive from one or more transmissionsource simultaneously and/or separately (in time domain), and/or tooperate using (e.g., receiving) two or more antenna portssimultaneously, and/or may be connected and/or connectable and/orcomprise multiple independently operable or controllable antennas orantenna arrays or subarrays.

An allocation unit may be considered to be associated to referencesignaling or a reference signaling sequence if it carries at least acomponent of the reference signaling (e.g., a component of referencesignaling is transmitted on the allocation unit). An allocation unit mayin particular represent a time interval, e.g. a block symbol or theduration of a SC-FDM symbol, or OFDM symbol or equivalent, and/or may bebased on the numerology used for the synchronisation signaling, and/ormay represent a predefined time interval. The duration (in time domain)of an allocation unit may be associated to a bandwidth in frequencydomain, e.g. a subcarrier spacing or equivalent, e.g. a minimum usablebandwidth and/or a bandwidth of an allocation unit. It may be consideredthat signaling spanning an allocation unit corresponds to the allocationunit (time interval) carrying the signaling and/or signaling beingtransmitted (or received) in the allocation unit. Transmission ofsignaling and reception of signaling may be related in time by a pathtravel delay the signaling requires to travel from the transmitter toreceiver (it may be assumed that the general arrangement in time isconstant, with path delay/multi path effects having limited effect onthe general arrangement of signaling in time domain). Allocation unitsassociated to different signalings, e.g. different reference signalings,in particular on different ports or TPs. may be considered to beassociated to each other and/or correspond to each other if theycorrespond to the same number of allocation unit within a referencesignaling transmission time interval, and/or if they are synchronised toeach other and/or are simultaneous, e.g. in two simultaneoustransmissions. Similar reasoning may pertain to a transmission timeinterval; the same interval for two signalings may be the intervalshaving the same number and/or relative location in the frame or timingstructure associated to each signaling.

A reference signaling sequence (or shorter, signaling sequence) maycorrespond to a sequence of modulation symbols (e.g., in time domain,after DFT-spreading for a SC-FDM system, or in frequency domain for anOFDM system). The signaling sequence may be predefined. The set ofmodulation symbols used for the signaling sequence may be different fromthe set of modulation symbols used for communication signaling; inparticular, the reference signaling and/or signaling sequence mayrepresent different constellations in modulation and/or phase space thanthe communication signaling.

There is also described a program product comprising instructionscausing processing circuitry to control and/or perform a method asdescribed herein.

Moreover, a carrier medium arrangement carrying and/or storing a programproduct as described herein is considered. An information systemcomprising, and/or connected or connectable, to a radio node is alsodisclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are provided to illustrate concepts and approachesdescribed herein, and are not intended to limit their scope. Thedrawings comprise:

FIG. 1, showing an exemplary signaling scenario;

FIG. 2, showing an exemplary (e.g., feedback) radio node; and

FIG. 3, showing another exemplary (e.g., signaling) radio node.

DETAILED DESCRIPTION

In the following, concepts are explained with reference to NR, inparticular according to Rel. 16.4 or higher. However, the concepts andapproaches may be applicable to other systems and technology, e.g. withfunctionality allowing transmission of PTRS or equivalent referencesignaling with signaling on single or multiple transmission sources orTRPs.

In NR, phase tracking reference signal (PT-RS) can be configured forPDSCH transmissions in order for the receiver to correct phase noiserelated errors. PT-RS can be configured with the higher layer parameterphase Tracking RS in dmrs-DownlinkForPDSCH-MappingTypeA ordmrs-DownlinkForPDSCH-MappingTypeB for PDSCH scheduled by DCI format 1_0or DCI format 1_1, or in dmrs-DownlinkForPDSCH-MappingTypeA-DCI-1-2 ordmrs-DownlinkForPDSCH-MappingTypeB-DCI1-2 for PDSCH scheduled with DCIformat 1_2.

In the frequency domain, a PT-RS may be in at most one subcarrier perevery 2 PRBs. Also, the subcarrier used for a PT-RS port may be one ofthe subcarriers also used for the DM-RS port associated with the PT-RSport (note that PT-RS may be not transmitted for DMRS carrying symbols).For DMRS configuration type 1, a DMRS port is mapped to every secondsubcarrier. Consequently, an associated PT-RS can only be mapped to oneout of 6 subcarriers. An offset can be configured to determine whichsubcarrier the DM-RS is mapped to.

In the time domain, the time domain density of PT-RS may be a functionof the scheduled MCS. The PT-RS time density may for example be one of1,2 or 4, corresponding to PT-RS in every OFDM symbol, every second OFDMsymbols, or every fourth OFDM symbol in a slot, respectively, which maybe determined based on the scheduled MCS. For low MCS values (i.e.,I_(MCS)<ptrs-MCS₁), PT-RS may be not transmitted as downlink symbolreception is not very sensitive to phase noise at low MCSs. Themodulated symbol used for the PT-RS may be the same as the associatedDMRS at the same subcarrier. If a UE is scheduled with one codeword, thePT-RS antenna port is associated with the lowest indexed DM-RS antennaport among the DM-RS antenna ports assigned for the PDSCH. If a UE isscheduled with two codewords (two independent transmissions), the PT-RSantenna port is associated with the lowest indexed DM-RS antenna portamong the DM-RS antenna ports assigned for the codeword with the higherMCS. If the MCS indices of the two codewords are the same, the PT-RSantenna port is associated with the lowest indexed DM-RS antenna portassigned for codeword 0.

An important aspect is that PT-RS may never be present when using DM-RSports 1004-1007 for DMRS Type 1 and ports 1006-1011 for DMRS Type 2.When PT-RS is present, the maximum rank is 6.

The PT-RS transmit power may be boosted when the PDSCH contains morethan one spatial layer. In other words, the ratio of PT-RS energy perresource element (EPRE) to PDSCH EPRE per layer (ρ_(PTRS)) can begreater than OdB. This is because for PT-RS, only a single layer istransmitted while PDSCH can have multiple layers. For the same totalEPRE, per layer EPRE for PT-RS can be larger than for PDSCH when thePDSCH has more than one layer.

The PDSCH PT-RS symbols may be scaled by a factor

$\beta_{PTRS} = {10^{\frac{\rho_{PTRS}}{20}}.}$

In NR Rel-16, non-coherent joint transmission (NC-JT) of PDSCH from twoTRPs was introduced, in which different layers of a PDSCH aretransmitted from different TRP. This is indicated to a UE by signalingtwo Transmission Configuration Indicator (TCI) states and DMRS ports intwo CDM groups in a DCI scheduling the PDSCH, where a first TCI state isassociated with a first CDM group and a second TCI state is associatedwith a second CDM group. The first and the second TCI states areassociated with a first and a second TRP, respectively.

A TCI state is used in NR to indicate a so called quasi co-location(QCL) relationship between two antenna ports. QCL describes thelarge-scale channel properties such Doppler shift/spread, average delayspread, or average delay. If antenna ports A and B are QCLed withrespect to average delay, the UE can estimate the average delay from thesignal received from antenna port A (known as the source referencesignal (RS)) for antenna port B (target RS). The target RS is DMRS inTCI states for PDSCH.

An example is shown FIG. 1, where a PDSCH with 3 layers is transmittedfrom two TRPs with the first two layers transmitted from TRP #1 and thethird layer from TRP #2. TRP#1 is associated with TCI state i and TRP #2is associated with TCI state j. The first two layers are associated DMRSports 0 and 1 in CDM group 0 and the third layer is associated with DMRSport 2 in CDM group 1.

When a PDSCH with multiple layers is scheduled from two TRPs, a subsetof the layers is transmitted from each of the two TRPs. Since differentfrequency sources may be used in different TRPs, the generated phasenoise can be different. Therefore, two PT-RS ports were introduced in NRRel-16, and each PT-RS port is transmitted from one of the two TRPs. Inthis case, because different power amplifiers are used in the two TRPs,power cannot be shared between layers across the TRPs. Thus, the amountof PT-RS power allocation for a PT-RS port would depend on only thenumber of PDSCH layers scheduled from the same TRP.

For example, consider the example where a PDSCH with 3 layers arescheduled with 2 layers over TRP #1 and 1 layer over TRP #2. DMRS ports#0 and #1 are associated with the TRP #1 and DMRS port #2 with TRP #2.If two PT-RS ports are configured, PT-RS port #0 is associated with DMRSport #0 and PT-RS port #1 is associated with DMRS port #2. Then, thepower boosting ratio for PT-RS port #0 can be up to 3dB, while for PT-RSport #1, no power boosting can be done. Therefore, in general the amountof power boosting for the two PT-RS ports can be different.

When different layers of a PDSCH are transmitted from two different TRPsand two PT-RS ports are configured, one associated to each TRP, theexisting PT-RS power allocation does not fully utilize the allocatedtransmit power from each TRP. A new downlink PT-RS power allocation maybe considered for NC-JT based PDSCH transmission from two TRPs, in whichPT-RS power can be further boosted without reducing the PDSCH transmitpower. More transmit power can be used for PT-RS transmission withoutreducing the PDSCH transmit power and thus, better phase trackingperformance can be achieved.

In case of NC-JT based PDSCH transmission from two TRPs, the REs fortransmitting a PT-RS port from one TRP are not used in the other TRP forany purpose, i.e., the REs may be blanked out in the other TRP.

Reverting to FIG. 1, Error! Reference source not found.a PDSCH with 3layers is scheduled from two TRPs. The first two layers are associatedwith DMRS ports 0 and 1 and are transmitted from TRP #1. The third layeris associated with DMRS port 2 and is transmitted from TRP #2. For phasetracking purpose, two PT-RS ports are configured. PT-RS port 0 istransmitted from TRP #1 and PT-RS port 1 is transmitted from TRP #2.Note that the two PT-RS ports are present in different subcarriers ofthe same RBs and have the same density in both time and frequency. Also,two PT-RS ports are present in the same OFDM symbols. Thus, for eachTRP, the power allocated in the blanked out RE can be used to increaseor boost the PT-RS transmit power by 3dB from that TRP while keeping thesame average PDSCH transmit power as well as total transmit power (PDSCHand PT-RS) as that when the REs are used for PDSCH transmission.

The ratio of PT-RS EPRE to PDSCH EPRE per layer per RE (ρ_(PTRS)) foreach of the two PT-RS ports can be increased accordingly when two PT-RSports are configured. For example, a new row may be added in Table 4.1-2of 3 gpp TS 38.214 v16.4.0 (or later), or the existing row withepre-ratio=0 may be modified. Table 1 shows an example in which thefirst row (i.e., with epre-ratio=0) is modified such that the ratiosdepend on the number of PT-RS ports, Qp. When a single PT-RS port isconfigured, i.e., Qp=1, the ratios for epre-Ratio=0 is the same asratios in existing Table 4.1-2 of 3 gpp TS 38.214 v16.4.0. When twoPT-RS ports are configured and NC-JT based PDSCH transmission isindicated, i.e., Qp=2, the ratio is increased by 3 dB.

TABLE 1 The ratio of PT-RS EPRE to PDSCH EPRE per layer per RE(ρ_(PTRS)) The number of PDSCH layers with DM-RS epre- associated to thePT-RS port Ratio 1 2 3 4 5 6 0 3Qp − 3 3Qp 3Qp + 1.77 3Qp + 3 3Qp + 43Qp + 4.77 1 0 0 0 0 0 0 2 reserved 3 reserved

Table 2 shows another example in which a new row with epre-ratio=2 isadded.

TABLE 2 The ratio of PT-RS EPRE to PDSCH EPRE per layer per RE(ρ_(PTRS)) The number of PDSCH layers with DM-RS epre- associated to thePT-RS port Ratio 1 2 3 4 5 6 0 0 3 4.77 6 7 7.78 1 0 0 0 0 0 0 2 3Qp − 33Qp 3Qp + 1.77 3Qp + 3 3Qp + 4 3Qp + 4.77 3 reserved

When 2 PT-RS ports are configured, a PDSCH can still be scheduled from asingle TRP by indicating a single TCI state in the corresponding DCI. Inthat case, one PT-RS port is transmitted together with the PDSCH.Therefore, Qp is the actual number of the PT-RS ports associated with aPDSCH, not the higher layer configured number of PT-RS ports. In 3GPPspecifications, a rule may be specified where Qp=2 when all thefollowing conditions are met:

2 downlink PT-RS ports may be configured in the PTRS-DownlinkConfiginformation element (i.e., maxNrofPorts-r16 in PTRS-DownlinkConfig isset to n2), 2 TCI states may be indicated in the TCI field of the DCIthat schedules the PDSCH, and

DM-RS ports associated with the PDSCH belong to two CDM groups.

The above embodiment applies to the case when a single DCI is used toschedule a 1^(st) set of layers from TRP#1 and a 2^(nd) set of layersfrom TRP#2 where the union of both sets are within the same PDSCH (eachset may comprise one or more layers, different sets may comprisedifferent numbers of layers). In this case the REs used by TRP#2 for the2^(nd) PTRS port are muted in the transmission from TRP#1 and viceversa. This ensures that there is no PDSCH to PTRS interference betweenlayers, and thus phase noise can be effectively compensated.

A variation of the above embodiment may apply to the case when multi-DCIscheduling is used to schedule two separate PDSCHs, one from each TRP.This is indicated by configuring the UE with a plurality of CORESETs(Control resource sets) in which a first subset of the CORESETs isconfigured with a CORESET Pool ID that is different than for a second(mutually exclusive) subset of CORESETs. In this, case, if a set ofaperiodic ZP-CSI-RS (zero power channel state information referencesignal) resources is triggered by the scheduling DCI transmitted fromTRP#1 (#2) such that the PDSCH transmitted from one TRP#1 (#2) is ratematched around the PTRS REs used by TRP#2, then the new row withepre-ratio=2 can be used for reception of the PTRS port associated withTRP#1 (#2). In other words, if each TRP mutes the REs associated withthe PTRS port transmitted by the other TRP, then larger PTRS powerboosting may be utilized by each TRP without reducing the PDSCH powerfrom each TRP.

In another embodiment, different PDSCH layers corresponding to differentcodewords may be transmitted from the two TRPs. Hence, different MCSscorresponding to the two codewords are also signaled as part of thescheduling DCI that schedules the PDSCH. An example where PDSCH layers 0and 1 are transmitted from TRP #1 and TRP #2, respectively, may beconsidered. In this example, PDSCH layer 0 corresponds to a firstcodeword while PDSCH layer 1 corresponds to a second codeword. The MCSscorresponding to the two codewords received from the two TRPs aredenoted as MCS1 and MCS2. PT-RS port 0 corresponds to TRP #1 and PT-RSport 1 corresponds to TRP #2. Since the time density of the PT-RS isdependent on the scheduled MCS, in this embodiment the time domaindensities of PT-RS port 0 and PT-RS port 1 can be different owing to thefact that MCS1 and MCS2 can be different due to different channelqualities between the UE and the two TRPs. The time domain densities ofPT-RS ports 0 and 1 are two and one, respectively.

An example of PDSCH transmission from two TRPs in which a first layer istransmitted from TRP #1 and a second layer is transmitted from TRP #2,and two PT-RS ports are configured, one associated with each TRP may beconsidered. In this embodiment, the power boosting for a PT-RS RE maydepend on the number of PT-RS ports in the OFDM symbol of that PT-RS RE.In the example, OFDM symbols 4, 6, 8, 10 and 12 may have two PT-RS portstransmitted, while OFDM symbols 3, 5, 7, 9, 11, and 13 have only onePT-RS port. In OFDM symbols 4, 6, 8, 10 and 12, for each TRP, the powerblanked out REs can be used to increase or boost the PT-RS transmitpower by 3 dB from that TRP while keeping the same average PDSCHtransmit power as well as total transmit power (PDSCH and PT-RS) as thatwhen the REs are used for PDSCH transmission. This power boost isapplicable to both PT-RS port 0 and 1 in OFDM symbols 4, 6, 8, 10, and12. However, in OFDM symbols 3, 5, 7, 9, 11, and 13, there is only asingle PT-RS port, hence no such increase or boost of PT-RS transmitpower is done for PT-RS port 1.

Table 3 shows an example in which the first row (i.e., withepre-ratio=0) is modified such that the ratios depend on the number ofPT-RS ports in an OFDM symbol t, which is denoted by Q_(p,t). When asingle PT-RS port is transmitted in OFDM symbol t, then Q_(p,t)=1. Whentwo PT-RS ports are transmitted in OFDM symbol t, then Q_(p,t)=2.

TABLE 3 The ratio of PT-RS EPRE to PDSCH EPRE per layer per RE(ρ_(PTRS)) The number of PDSCH layers with DM-RS epre- associated to thePT-RS port Ratio 1 2 3 4 5 6 0 3Q_(p, t) − 3Q_(p, t) 3Q_(p, t) +3Q_(p, t) + 3Q_(p, t) + 3Q_(p, t) + 3 1.77 3 4 4.77 1 0 0 0 0 0 0 2reserved 3 reserved

Table 4 shows another example in which a new row with epre-ratio=2 isadded such that the ratios depend on the number of PT-RS ports in anOFDM symbol t, which is denoted by O_(p,t).

TABLE 4 The ratio of PT-RS EPRE to PDSCH EPRE per layer per RE(ρ_(PTRS)) The number of PDSCH layers with DM-RS epre- associated to thePT-RS port Ratio 1 2 3 4 5 6 0 0 3 4.77 6 7 7.78 1 0 0 0 0 0 0 23Q_(p, t) − 3Q_(p, t) 3Q_(p, t) + 3Q_(p, t) + 3Q_(p, t) + 3Q_(p, t) + 31.77 3 4 4.77 3 reserved

Single DCI based NC-JT may be considered. If a UE is configured by thenetwork with two PT-RS ports for PDSCH transmissions (i.e., the higherlayer parameter “maxNrofPorts-r16” is set to “n2” in“PTRS-DownlinkConfig” in TS38.331 v16.3.0), and

-   -   1) if a PDSCH is scheduled to the UE with a DCI indicating two        TCI states, DMRS ports in two CDM groups, and a single MCS, 3 dB        more power can be allocated to each of the two PT-RS ports        associated with the PDSCH.

The ratio, ρ_(PTRS) ^(p), of PT-RS EPRE to PDSCH EPRE per layer for aPT-RS port p (p=0,1) associated with a PDSCH can be determined as

ρ_(PTRS) ^(p) =R _(p) Q _(p) or ρ_(PTRS) ^(p)(dB)=10log10(R_(p))+10log10(Q _(p))

where Q_(p) is the actual number of PT-RS ports transmitted with thePDSCH, and R_(p) is the number of MIMO layers associated with PT-RS portp in the PDSCH

-   -   2) if a PDSCH is scheduled to the UE with a DCI indicating two        TCI states, DMRS ports in two CDM groups, and two MCS each        associated to one of the two TCI states, the amount of        additional PT-RS power boosting is OFDM symbol dependent

The ratio, ρ_(PTRS) ^(p,t), of PT-RS EPRE to PDSCH EPRE per layer for aPT-RS port ρ at OFDM symbol t associated with a PDSCH can be determinedas

ρ_(PTRS) ^(p) =R _(p) Q _(p,t) or ρ_(PTRS) ^(p,t)(dB)=10log10(R_(p))+10log10(Q _(p,t))

where Q_(p,t) is the actual number of PT-RS ports transmitted with thePDSCH in OFDM symbol t, and R_(p) is the number of MIMO layersassociated with PT-RS port p in the PDSC Multi-DCI based NC-JT may beconsidered. If a UE is configured by the network with one PT-RS port forPDSCH (i.e., the higher layer parameter “maxNrofPorts-r16”is set to “n1”in “PTRS-DownlinkConfig” in TS38.331 v16.3.0) and with multiple CORESETshaving different CORESET pool indices in a bandwidth part (BWP), if afirst PDSCH with a first PTRS port is scheduled to the UE with a firstDCI, and a second PDSCH with a second PTRS port is scheduled to the UEwith a second DCI in a same slot. A first and second sets of aperiodicZP CSI-RS resources can be used to indicate the resources of the secondand first PTRS ports in the first and second DCIs, respectively. Thepower for each of the PTRS ports can be boosted by 3 dB. The ratio,ρ_(PTRS) ^(p), of PT-RS EPRE to PDSCH EPRE per layer for a PT-RS port pcan be determined as ρ_(PTRS) ^(p)=2R_(p) or ρ_(PTRS) ^(p)(dB)=3dB+10log10(R_(p)), where R_(p) is the number of MIMO layers associatedwith PT-RS port p.

In general, it may be considered that for multi-TRP transmission,resources like resource elements used for PT-RS by one TRP may be mutedor not used for transmission by the other TRP or TRPs.

An alternative clustered structure for a phase tracking reference signal(PT-RS) may be considered. PTRS may be clustered in the frequency domainto create a block of contiguous known symbols. To deal with dispersivechannels and capture frequency diversity gains, for example, amulti-cluster block PTRS structure may for example have N PTRS clustersand each cluster consists of M PTRSs. A cyclic PTRS sequence may be usedin each of the block PTRS cluster. That is, the ending portion of thePTRS sequence may identical to the starting portion of said sequence,and/or the PTRS may be considered to be cyclically extended in eachcluster or continuous block. The advantage of the cyclic PTRS sequenceis the possibility to use a lower complexity ICI filter estimationalgorithm though at some cost of performance degradation. When using adistributed PTRS structure for CP-OFDM, in single-DCI based multi-TRPtransmission with one PTRS port configured for each TRP, the PTRSsubcarriers corresponding to two different TRPs may be located next toeach other. Meanwhile, to avoid PDSCH to PTRS interference caused bymulti-TRP transmission, the PTRS subcarriers associated with the secondTRP may be muted in the transmission from the first TRP and vice versa.As such, a direct de-ICI algorithm utilizing the PDSCH subcarriersimmediately adjacent to the PTRS subcarriers for de-ICI filterestimation, cannot be re-used directly to the multi-TRP transmissionscenario.

In an exemplary PTRS frequency distribution, specifically an exemplaryPTRS structure for two TRPs with a density setting K=2 for thesubcarriers used for PTRS for each TRP, such that every second PRBcarries PTRS. It can be observed that subcarriers used for PTRS from thetwo TRPs are adjacent to each other. For the signal transmitted fromTRP1 (TRP2), the subcarriers used for PTRS for TRP2 (TRP1) are muted,e.g., zero power transmission is used on these sub-carriers.

A frequency merged block PTRS structure for multi-TRP transmissions withcyclic PTRS sequences (an example for a clustered distribution) may beconsidered, for which PTRS from the two TRPs may be adjacent to eachother. For the signal transmitted from TRP1 (TRP2), the subcarriers usedfor PTRS for TRP2 (TRP1) are muted, e.g., zero power transmission isused on these sub-carriers. From the receiver perspective, PTRS fromdifferent TRPs are on contiguous and/or neighboring subcarriers in ablock or cluster, covering N>2 subcarriers or M>1 PRBs.

In general, it may be considered that for multi-TRP transmission,resources like resource elements used for PT-RS by one TRP are muted ornot used for transmission by the other TRP or TRPs. An alternativeclustered structure for a phase tracking reference signal (PT-RS) may beconsidered, in particular for multi-TRP cases.

Scenarios with transmissions from multiple transmission sources and/ormultiple TRPs and/or multiple PTRS ports may be considered. DifferentTRPs may be numbered, e.g. as TRP1, TRP2, . . . . The examples may referto two TRPs, but more than two TRPs may be utilised analogously.Reference may be made to TRP only for brevity; however, such referencesmay be interpreted to refer to a transmission source or PTRS port orassociated DMRS port instead. In general, there may be transmission ofsignaling (and/or reception) comprising the PTRS as described herein. Ingeneral, each subcarrier may carry PTRS at most from one TRP ortransmission source. A subcarrier carrying PTRS of one TRP may beconsidered to be associated to that TRP (and vice versa). It may beconsidered that a subcarrier carrying PTRS refers to a modulation symbolof the PTRS being transmitted or carried on the subcarrier, e.g. basedon a signaling sequence for the PTRS. Each PRB may in general comprise12 subcarriers, or, for other systems than NR, a different number.

In general, a distributed PTRS arrangement or distribution may refer toscenarios in which a PRB has at most one subcarrier carrying PTRS fromone (the same) TRP, or in some cases, at most two subcarriers (which maybe neighbouring in frequency domain, or in some cases, not), and/or noneighbouring subcarriers (in frequency domain) carrying PTRS from thesame PTRS. A PRB may have (different) subcarriers carrying PTRS frommore than one TRP, unless specifically stated otherwise.

A cluster or block arrangement or distribution of PTRS may refer ingeneral to a distribution in which a PRB has more than one or more thantwo subcarriers carrying PTRS from one TRP, in particular 4 or more. Thesubcarriers may be neighbouring in frequency domain, or be apart. To beapart, they may for example be interleaved or interlaced such thatbetween two subcarriers associated to one TRP, there is arranged one ormore subcarrier associated to another TRP and/or one or more emptysubcarriers and/or subcarriers carrying data or control information maybe arranged between two subcarriers associated to one TRP. This mayrefer to the same OFDM or SCFDM symbol or the same allocation unit,and/or pertain to simultaneous transmission of the PTRS.

In general, it may be considered that a network node configures awireless device for receiving first and second signaling, e.g. asindicated herein. The configuring may be performing using RRC signaling,and/or MAC layer signaling, and/or in some cases DCI signaling may beused, e.g. to indicate a configuration provided with higher layersignaling like RRC signaling or RLC signaling.

FIG. 2 schematically shows a radio node, in particular a wireless deviceor terminal 10 or a UE (User Equipment). Radio node 10 comprisesprocessing circuitry (which may also be referred to as controlcircuitry) 20, which may comprise a controller connected to a memory.Any module of the radio node 10, e.g. a communicating module ordetermining module, may be implemented in and/or executable by, theprocessing circuitry 20, in particular as module in the controller.Radio node 10 also comprises radio circuitry 22 providing receiving andtransmitting or transceiving functionality (e.g., one or moretransmitters and/or receivers and/or transceivers), the radio circuitry22 being connected or connectable to the processing circuitry. Anantenna circuitry 24 of the radio node 10 is connected or connectable tothe radio circuitry 22 to collect or send and/or amplify signals. Radiocircuitry 22 and the processing circuitry 20 controlling it areconfigured for cellular communication with a network, e.g. a RAN asdescribed herein, and/or for sidelink communication (which may be withincoverage of the cellular network, or out of coverage; and/or may beconsidered non-cellular communication and/or be associated to anon-cellular wireless communication network). Radio node 10 maygenerally be adapted to carry out any of the methods of operating aradio node like terminal or UE disclosed herein; in particular, it maycomprise corresponding circuitry, e.g. processing circuitry, and/ormodules, e.g. software modules. It may be considered that the radio node10 comprises, and/or is connected or connectable, to a power supply.

FIG. 3 schematically shows a radio node 100, which may in particular beimplemented as a network node 100, for example an eNB or gNB or similarfor NR. Radio node 100 comprises processing circuitry (which may also bereferred to as control circuitry) 120, which may comprise a controllerconnected to a memory. Any module, e.g. transmitting module and/orreceiving module and/or configuring module of the node 100 may beimplemented in and/or executable by the processing circuitry 120. Theprocessing circuitry 120 is connected to control radio circuitry 122 ofthe node 100, which provides receiver and transmitter and/or transceiverfunctionality (e.g., comprising one or more transmitters and/orreceivers and/or transceivers). An antenna circuitry 124 may beconnected or connectable to radio circuitry 122 for signal reception ortransmittance and/or amplification. Node 100 may be adapted to carry outany of the methods for operating a radio node or network node disclosedherein; in particular, it may comprise corresponding circuitry, e.g.processing circuitry, and/or modules. The antenna circuitry 124 may beconnected to and/or comprise an antenna array. The node 100,respectively its circuitry, may be adapted to perform any of the methodsof operating a network node or a radio node as described herein; inparticular, it may comprise corresponding circuitry, e.g. processingcircuitry, and/or modules. The radio node 100 may generally comprisecommunication circuitry, e.g. for communication with another networknode, like a radio node, and/or with a core network and/or an internetor local net, in particular with an information system, which mayprovide information and/or data to be transmitted to a user equipment.

Aspects regarding QCL may be considered. For example, several signalsmay be transmitted from different antenna ports and/or transmissionsources associated to the same base station at a same or different time.If these signals have the same large-scale properties such as Dopplershift/spread, average delay spread, or average delay, these antennaports are said to be quasi co-located (QCL) with respect to thelarge-scale properties. If a UE knows that two antenna ports are QCLwith respect to a certain parameter (e.g. Doppler spread), the UE canestimate that parameter based on a first antenna port and apply thatestimate for receiving signal on the second antenna port. Typically, ameasurement reference signal (RS) such as NZP CSI-RS (Non-Zero PowerChannel State Information Reference Signal) or SSB (SynchronizationSignal Block), known as source RS, is sent on the first antenna andanother signal such as a demodulation reference signal (DMRS), known astarget RS, is sent on the second antenna port. For instance, if antennaports A and B are QCL with respect to average delay, the UE can estimatethe average delay from the signal received from antenna port A andassume that the signal received from antenna port B has the same averagedelay. This is useful for demodulation because in some scenarios,certain channel properties cannot be reliably estimated based on signals(e.g., DMRS) received on port B. With the QCL relation, the UE can firstmeasure certain channel properties on antenna port A and apply anappropriate channel estimation filter when receiving signals on antennaport B. Information about what assumptions can be made regarding QCL issignaled to the UE from the network. In NR, four types of QCL relationsbetween a transmitted source RS and transmitted target RS were defined:

Type A: {Doppler shift, Doppler spread, average delay, delay spread}

Type B: {Doppler shift, Doppler spread}

Type C: {average delay, Doppler shift}

Type D: {Spatial Rx parameter}

QCL type D is known as spatial QCL. There is currently no strictdefinition of spatial QCL, but the understanding is that if twotransmitted antenna ports are spatially QCL, the UE can use the same Rxbeam to receive them.

TCI states may be considered. A QCL relation between two RS may besignaled or indicated to a UE or wireless device through so called TCI(Transmission Configuration Indicator) states. Each TCI state cancontain one or two source RS and associated QCL type. For example, a TCIstate may contain a pair of source RS and QCL types, e.g., {NZP CSI-RS1,QCL Type A} and {NZP CSI-RS2, QCL Type D}. In this example, the UE canderive Doppler shift, Doppler spread, average delay, delay spread fromNZP CSI-RS1 and Spatial Rx parameter (i.e. the RX beam to use) from NZPCSI-RS2. A TCI state can be interpreted as a possible beam transmittedfrom the network and/or a possible TRP (Transmission Point) used by thenetwork to communicate with the UE. A UE may be configurable through RRCsignaling, e.g. with up to 8 TCI states in FR1 and 128 TCI states in FR2for PDSCH, depending on UE capability. Up to 8 TCI states per BWP(Bandwidth Part) per serving cell may be activated by MAC (Medium AccessControl) CE (Control Element). The UE determines QCL for a PDSCHreception based on the TCI-State(s) indicated in the ‘TransmissionConfiguration Indication’ field in a DCI scheduling the PDSCH. A mappingbetween a TCI codepoint in DCI and one or two TCI states may be providedin the enhanced PDSCH MAC CE that activates the TCI states.

In some variants, a search space set may be defined over a CORESET. ACORESET may consist of N_(RB) ^(CORESET) resource blocks in thefrequency domain and N_(symb) ^(CORESET)∈{1,2,3} consecutive OFDMsymbols in the time domain. For each DL BWP configured to a UE in aserving cell, a UE may be provided by higher layer signalling with P≤5CORESETs. For each CORESET, a UE may be configured by RRC (RadioResource Control) signaling with CORESET information element (IE), whichmay include one or more of:

-   -   ControlResourceSetld: a CORESET index ^(p),0≤p≤16;    -   a DM-RS scrambling sequence initialization value;    -   a list of up to 64 TCI-States can be configured in a CORESET p;    -   an indication for a presence or absence of a transmission        configuration indication (TCI) field for DCI format 1_1        transmitted by a PDCCH in CORESET ^(p). The corresponding field        for indicating a presence or absence of a TCI field for DCI        format 1_2 is given by ‘tci-PresentInDCI-ForDCIFormat1_2’.

In general, for each CORESET or control region, one TCI state may beactivated and/or associated, e.g. by a MAC CE transmitted by a networknode.

Single-DCI based DL data transmission over Multiple Transmission Points(TRP) may be considered. A PDSCH, which in general may correspond todata signaling, and/or a data block (in particular, a transport block orcode block bundle) may be transmitted to a UE from multiple TRPs. Sincedifferent TRPs may be located in different physical locations and/orhave different beams, the propagation channels can be different. Tofacilitate receiving PDSCH data from different TRPs or beams, a UE maybe indicated with two TCI states, each associated with a TRP or a beam,by a single codepoint of a TCI field in a DCI. The network may configurethe UE with multiple TCI states via RRC. Whether a codepoint in the TCIfield is mapped to one or two TCI states may be provided by an enhancedPDSCH MAC CE that activates the TCI states.

As one example of PDSCH transmission over two TRPs, a case may beconsidered in which different layers of a PDSCH are sent over two TRPs,each associated with a different TCI state. In this case, two DMRSports, one for each layer, in two CDM (Code Division Multiplex, shiftedby different codes) groups may also be signaled to the UE. A first TCIstate is associated with the DMRS port in a first CDM group, and asecond TCI state is associated with the DMRS port in a second CDM group.This approach may be referred to as NC-JT (Non-coherent jointtransmission) or scheme In this context, a single CW (codeword, e.g.associated to one data block) may be transmitted over two TRPs.

Transmitting PDSCH over multiple TRPs can also be used to improve PDSCHtransmission reliability. For example, a PDSCH may be sent over TRP1 inPRGs (precoding RB group) {0,2,4} and over TRP2 in PRGs {1,3,5}. ThePDSCH is scheduled by a PDCCH or DCI which may be sent over TRP1, i.e.associated with TCI state 1. In another variant, PDSCH Occasion #1 maybe transmitted in PRGs {0,2,4} from TRP1 and PDSCH Occasion #2 with thesame TB may be transmitted in PRGs {1,3,5} from TRP2. The two PDSCHOccasions may carry the same encoded data payload, and may have thesame, or different redundancy version; the UE or wireless device mayperform soft combining of the two PDSCHs to achieve more reliablereception.

In some cases, data transmission with PDSCH repetition may be utilised,e.g. such that repetition of one PDSCH (e.g., codeword and/or datablock) may occurs within a slot, with different transmission sources orTRP (e.g., with different QCL or TCI) transmitting different occasionsof the repetitions. For example, each transmission may be in a mini slotof 4 OFDM symbols within a slot; transmission in different mini-slotsmay be provided by different transmission sources or TRPs. Each PDSCHtransmission may be associated with a same or different RV. For theseschemes, a single DCI transmitted from one TRP may be used to schedulemultiple PDSCH transmissions over two TRPs.

Alternatively, Multi-DCI based PDSCH transmission with multiple TRPs maybe considered. Multi-DCI scheduling for multi-TRP may refer to cases inwhich a UE or WD may receive two or more DCIs, each DCI scheduling aPDSCH. Each PDCCH and the corresponding (scheduled) PDSCH may betransmitted from the same TRP. For example, a PDSCH1 may be scheduled byPDCCH 1 from TRP1, and PDSCH2 may be scheduled by PDCCH 2 from TRP2. Thetwo PDSCHs may be fully, partially, or non-overlapping in time and/orfrequency. When the two PDSCHs are fully or partially overlapping, asame DMRS resource configuration may be assumed with DMRS ports of thetwo PDSCHs in different CDM groups and/or shifted relative to each otheraccording to another approach. For multi-DCI operation, a UE may beconfigured with two CORESET pools, each associated with a TRP. EachCORESET pool may correspond to a collection of CORESETs that belongs tothe same pool. A CORESET pool index can be configured in each CORESET,e.g. with a value of 0 or 1. For the two Das in the above example, theymay be transmitted in two CORESETs belonging to different CORESET pools(i.e. with CORESETPoolIndex 0 and 1 respectively). The two PDSCHs may beassociated to, and/or belong to, two different HARQ processes. Formulti-DCI based PDSCH scheduling, TCI state activation and mapping tocodepoints of the TCI field in DCI may be per CORESET pool; only asingle TCI state may be mapped to a codepoint of TCI field in DCI. Thismeans that a DCI sent in a CORESET pool can only schedule a PDSCH fromone TRP.

In general, a block symbol and/or an allocation unit may representand/or correspond to an extension in time domain, e.g. a time interval.A block symbol duration (the length of the time interval) may correspondto the duration of an OFDM symbol or a corresponding duration, and/ormay be based and/or defined by a subcarrier spacing used (e.g., based onthe numerology) or equivalent, and/or may correspond to the duration ofa modulation symbol (e.g., for OFDM or similar frequency domainmultiplexed types of signaling). It may be considered that a blocksymbol comprises a plurality of modulation symbols, e.g. based on asubcarrier spacing and/or numerology or equivalent, in particular fortime domain multiplexed types (on the symbol level for a singletransmitter) of signaling like single-carrier based signaling, e.g.SC-FDE or SC-FDMA (in particular, FDF-SC-FDMA or pulse-shaped SC-FDMA).The number of symbols may be based on and/or defined by the number ofsubcarrier to be DFTS-spread (for SC-FDMA) and/or be based on a numberof FFT samples, e.g. for spreading and/or mapping, and/or equivalent,and/or may be predefined and/or configured or configurable. A blocksymbol in this context may comprise and/or contain a plurality ofindividual modulation symbols, which may be for example 1000 or more, or3000 or more, or 3300 or more. The number of modulation symbols in ablock symbol may be based and/or be dependent on a bandwidth scheduledfor transmission of signaling in the block symbol. A block symbol and/ora number of block symbols (an integer smaller than 20, e.g. equal to orsmaller than 14 or 7 or 4 or 2 or a flexible number) may be a unit(e.g., allocation unit) used or usable or intended e.g. for schedulingand/or allocation of resources, in particular in time domain. To a blocksymbol (e.g., scheduled or allocated) and/or block symbol group and/orallocation unit, there may be associated a frequency range and/orfrequency domain allocation and/or bandwidth allocated for transmission.

An allocation unit, and/or a block symbol, may be associated to aspecific (e.g., physical) channel and/or specific type of signaling, forexample reference signaling. In some cases, there may be a block symbolassociated to a channel that also is associated to a form of referencesignaling and/or pilot signaling and/or tracking signaling associated tothe channel, for example for timing purposes and/or decoding purposes(such signaling may comprise a low number of modulation symbols and/orresource elements of a block symbol, e.g. less than 10% or less than 5%or less than 1% of the modulation symbols and/or resource elements in ablock symbol). To a block symbol, there may be associated resourceelements; a resource element may be represented in time/frequencydomain, e.g. by the smallest frequency unit carrying or mapped to (e.g.,a subcarrier) in frequency domain and the duration of a modulationsymbol in time domain. A block symbol may comprise, and/or to a blocksymbol may be associated, a structure allowing and/or comprising anumber of modulation symbols, and/or association to one or more channels(and/or the structure may dependent on the channel the block symbol isassociated to and/or is allocated or used for), and/or referencesignaling (e.g., as discussed above), and/or one or more guard periodsand/or transient periods, and/or one or more affixes (e.g., a prefixand/or suffix and/or one or more infixes (entered inside the blocksymbol)), in particular a cyclic prefix and/or suffix and/or infix. Acyclic affix may represent a repetition of signaling and/or modulationsymbol/s used in the block symbol, with possible slight amendments tothe signaling structure of the affix to provide a smooth and/orcontinuous and/or differentiable connection between affix signaling andsignaling of modulation symbols associated to the content of the blocksymbol (e.g., channel and/or reference signaling structure). In somecases, in particular some OFDM-based waveforms, an affix may be includedinto a modulation symbol. In other cases, e.g.

some single carrier-based waveforms, an affix may be represented by asequence of modulation symbols within the block symbol. It may beconsidered that in some cases a block symbol is defined and/or used inthe context of the associated structure.

In some variants, a reference beam and/or reference beams and/orreference signaling may correspond to and/or carry random accesssignaling, e.g. a random access preamble. Such a reference beam orsignaling may be transmitted by another radio node. The signaling mayindicate which beam is used for transmitting. Alternatively, thereference beams may be beams receiving the random access signaling.Random access signaling may be used for initial connection to the radionode and/or a cell provided by the radio node, and/or for reconnection.Utilising random access signaling facilitates quick and early beamselection. The random access signaling may be on a random accesschannel, e.g. based on broadcast information provided by the radio node(the radio node performing the beam selection), e.g. withsynchronisation signaling (e.g., SSB block and/or associated thereto).The reference signaling may correspond to synchronisation signaling,e.g. transmitted by the radio node in a plurality of beams. Thecharacteristics may be reported on by a node receiving thesynchronisation signaling, e.g. in a random access process, e.g. a msg3for contention resolution, which may be transmitted on a physical uplinkshared channel based on a resource allocation provided by the radionode.

Data signaling may be on a data channel, for example on a PDSCH orPSSCH, or on a dedicated data channel, e.g. for low latency and/or highreliability, e.g. a URLLC channel. Control signaling may be on a controlchannel, for example on a common control channel or a PDCCH or PSCCH,and/or comprise one or more DCI messages or SCI messages. Referencesignaling may be associated to control signaling and/or data signaling,e.g. DM-RS and/or PT-RS.

Reference signaling, for example, may comprise DM-RS and/or pilotsignaling and/or discovery signaling and/or synchronisation signalingand/or sounding signaling and/or phase tracking reference signalingand/or cell-specific reference signaling and/or user-specific signaling,in particular CSI-RS. Reference signaling in general may be signalingwith one or more signaling characteristics, in particular transmissionpower and/or sequence of modulation symbols and/or resource distributionand/or phase distribution known to the receiver. Thus, the receiver canuse the reference signaling as a reference and/or for training and/orfor compensation. The receiver can be informed about the referencesignaling by the transmitter, e.g. being configured and/or signalingwith control signaling, in particular physical layer signaling and/orhigher layer signaling (e.g., DCI and/or RRC signaling), and/or maydetermine the corresponding information itself, e.g. a network nodeconfiguring a UE to transmit reference signaling. Reference signalingmay be signaling comprising one or more reference symbols and/orstructures. Reference signaling may be adapted for gauging and/orestimating and/or representing transmission conditions, e.g. channelconditions and/or transmission path conditions and/or channel (or signalor transmission) quality. It may be considered that the transmissioncharacteristics (e.g., signal strength and/or form and/or modulationand/or timing) of reference signaling are available for both transmitterand receiver of the signaling (e.g., due to being predefined and/orconfigured or configurable and/or being communicated). Different typesof reference signaling may be considered, e.g. pertaining to uplink,downlink or sidelink, cell-specific (in particular, cell-wide, e.g.,CRS) or device or user specific (addressed to a specific target or userequipment, e.g., CSI-RS), demodulation-related (e.g., DMRS) and/orsignal strength related, e.g. power-related or energy-related oramplitude-related (e.g., SRS or pilot signaling) and/or phase-related,etc.

References to specific resource structures like an allocation unitand/or block symbol and/or block symbol group and/or transmission timingstructure and/or symbol and/or slot and/or mini-slot and/or subcarrierand/or carrier may pertain to a specific numerology, which may bepredefined and/or configured or configurable. A transmission timingstructure may represent a time interval, which may cover one or moresymbols. Some examples of a transmission timing structure aretransmission time interval (TTI), subframe, slot and mini-slot. A slotmay comprise a predetermined, e.g. predefined and/or configured orconfigurable, number of symbols, e.g. 6 or 7, or 12 or 14. A mini-slotmay comprise a number of symbols (which may in particular beconfigurable or configured) smaller than the number of symbols of aslot, in particular 1, 2, 3 or 4, or more symbols, e.g. less symbolsthan symbols in a slot. A transmission timing structure may cover a timeinterval of a specific length, which may be dependent on symbol timelength and/or cyclic prefix used. A transmission timing structure maypertain to, and/or cover, a specific time interval in a time stream,e.g. synchronized for communication. Timing structures used and/orscheduled for transmission, e.g. slot and/or mini-slots, may bescheduled in relation to, and/or synchronized to, a timing structureprovided and/or defined by other transmission timing structures. Suchtransmission timing structures may define a timing grid, e.g., withsymbol time intervals within individual structures representing thesmallest timing units. Such a timing grid may for example be defined byslots or subframes (wherein in some cases, subframes may be consideredspecific variants of slots). A transmission timing structure may have aduration (length in time) determined based on the durations of itssymbols, possibly in addition to cyclic prefix/es used. The symbols of atransmission timing structure may have the same duration, or may in somevariants have different duration. The number of symbols in atransmission timing structure may be predefined and/or configured orconfigurable, and/or be dependent on numerology. The timing of amini-slot may generally be configured or configurable, in particular bythe network and/or a network node. The timing may be configurable tostart and/or end at any symbol of the transmission timing structure, inparticular one or more slots.

There is generally considered a program product comprising instructionsadapted for causing processing and/or control circuitry to carry outand/or control any method described herein, in particular when executedon the processing and/or control circuitry. Also, there is considered acarrier medium arrangement carrying and/or storing a program product asdescribed herein.

A carrier medium arrangement may comprise one or more carrier media.Generally, a carrier medium may be accessible and/or readable and/orreceivable by processing or control circuitry. Storing data and/or aprogram product and/or code may be seen as part of carrying data and/ora program product and/or code. A carrier medium generally may comprise aguiding/transporting medium and/or a storage medium. Aguiding/transporting medium may be adapted to carry and/or carry and/orstore signals, in particular electromagnetic signals and/or electricalsignals and/or magnetic signals and/or optical signals. A carriermedium, in particular a guiding/transporting medium, may be adapted toguide such signals to carry them. A carrier medium, in particular aguiding/transporting medium, may comprise the electromagnetic field,e.g. radio waves or microwaves, and/or optically transmissive material,e.g. glass fiber, and/or cable. A storage medium may comprise at leastone of a memory, which may be volatile or non-volatile, a buffer, acache, an optical disc, magnetic memory, flash memory, etc.

A system comprising one or more radio nodes as described herein, inparticular a network node and a user equipment, is described. The systemmay be a wireless communication system, and/or provide and/or representa radio access network.

Moreover, there may be generally considered a method of operating aninformation system, the method comprising providing information.Alternatively, or additionally, an information system adapted forproviding information may be considered. Providing information maycomprise providing information for, and/or to, a target system, whichmay comprise and/or be implemented as radio access network and/or aradio node, in particular a network node or user equipment or terminal.Providing information may comprise transferring and/or streaming and/orsending and/or passing on the information, and/or offering theinformation for such and/or for download, and/or triggering suchproviding, e.g. by triggering a different system or node to streamand/or transfer and/or send and/or pass on the information. Theinformation system may comprise, and/or be connected or connectable to,a target, for example via one or more intermediate systems, e.g. a corenetwork and/or internet and/or private or local network. Information maybe provided utilising and/or via such intermediate system/s. Providinginformation may be for radio transmission and/or for transmission via anair interface and/or utilising a RAN or radio node as described herein.Connecting the information system to a target, and/or providinginformation, may be based on a target indication, and/or adaptive to atarget indication. A target indication may indicate the target, and/orone or more parameters of transmission pertaining to the target and/orthe paths or connections over which the information is provided to thetarget. Such parameter/s may in particular pertain to the air interfaceand/or radio access network and/or radio node and/or network node.Example parameters may indicate for example type and/or nature of thetarget, and/or transmission capacity (e.g., data rate) and/or latencyand/or reliability and/or cost, respectively one or more estimatesthereof. The target indication may be provided by the target, ordetermined by the information system, e.g. based on information receivedfrom the target and/or historical information, and/or be provided by auser, for example a user operating the target or a device incommunication with the target, e.g. via the RAN and/or air interface.For example, a user may indicate on a user equipment communicating withthe information system that information is to be provided via a RAN,e.g. by selecting from a selection provided by the information system,for example on a user application or user interface, which may be a webinterface. An information system may comprise one or more informationnodes. An information node may generally comprise processing circuitryand/or communication circuitry. In particular, an information systemand/or an information node may be implemented as a computer and/or acomputer arrangement, e.g. a host computer or host computer arrangementand/or server or server arrangement. In some variants, an interactionserver (e.g., web server) of the information system may provide a userinterface, and based on user input may trigger transmitting and/orstreaming information provision to the user (and/or the target) fromanother server, which may be connected or connectable to the interactionserver and/or be part of the information system or be connected orconnectable thereto. The information may be any kind of data, inparticular data intended for a user of for use at a terminal, e.g. videodata and/or audio data and/or location data and/or interactive dataand/or game-related data and/or environmental data and/or technical dataand/or traffic data and/or vehicular data and/or circumstantial dataand/or operational data. The information provided by the informationsystem may be mapped to, and/or mappable to, and/or be intended formapping to, communication or data signaling and/or one or more datachannels as described herein (which may be signaling or channel/s of anair interface and/or used within a RAN and/or for radio transmission).It may be considered that the information is formatted based on thetarget indication and/or target, e.g. regarding data amount and/or datarate and/or data structure and/or timing, which in particular may bepertaining to a mapping to communication or data signaling and/or a datachannel. Mapping information to data signaling and/or data channel/s maybe considered to refer to using the signaling/channel/s to carry thedata, e.g. on higher layers of communication, with thesignaling/channel/s underlying the transmission. A target indicationgenerally may comprise different components, which may have differentsources, and/or which may indicate different characteristics of thetarget and/or communication path/s thereto. A format of information maybe specifically selected, e.g. from a set of different formats, forinformation to be transmitted on an air interface and/or by a RAN asdescribed herein. This may be particularly pertinent since an airinterface may be limited in terms of capacity and/or of predictability,and/or potentially be cost sensitive. The format may be selected to beadapted to the transmission indication, which may in particular indicatethat a RAN or radio node as described herein is in the path (which maybe the indicated and/or planned and/or expected path) of informationbetween the target and the information system. A (communication) path ofinformation may represent the interface/s (e.g., air and/or cableinterfaces) and/or the intermediate system/s (if any), between theinformation system and/or the node providing or transferring theinformation, and the target, over which the information is, or is to be,passed on. A path may be (at least partly) undetermined when a targetindication is provided, and/or the information is provided/transferredby the information system, e.g. if an internet is involved, which maycomprise multiple, dynamically chosen paths. Information and/or a formatused for information may be packet-based, and/or be mapped, and/or bemappable and/or be intended for mapping, to packets. Alternatively, oradditionally, there may be considered a method for operating a targetdevice comprising providing a target indicating to an informationsystem. More alternatively, or additionally, a target device may beconsidered, the target device being adapted for providing a targetindication to an information system. In another approach, there may beconsidered a target indication tool adapted for, and/or comprising anindication module for, providing a target indication to an informationsystem. The target device may generally be a target as described above.A target indication tool may comprise, and/or be implemented as,software and/or application or app, and/or web interface or userinterface, and/or may comprise one or more modules for implementingactions performed and/or controlled by the tool. The tool and/or targetdevice may be adapted for, and/or the method may comprise, receiving auser input, based on which a target indicating may be determined and/orprovided. Alternatively, or additionally, the tool and/or target devicemay be adapted for, and/or the method may comprise, receivinginformation and/or communication signaling carrying information, and/oroperating on, and/or presenting (e.g., on a screen and/or as audio or asother form of indication), information. The information may be based onreceived information and/or communication signaling carryinginformation. Presenting information may comprise processing receivedinformation, e.g. decoding and/or transforming, in particular betweendifferent formats, and/or for hardware used for presenting. Operating oninformation may be independent of or without presenting, and/or proceedor succeed presenting, and/or may be without user interaction or evenuser reception, for example for automatic processes, or target deviceswithout (e.g., regular) user interaction like MTC devices, of forautomotive or transport or industrial use. The information orcommunication signaling may be expected and/or received based on thetarget indication. Presenting and/or operating on information maygenerally comprise one or more processing steps, in particular decodingand/or executing and/or interpreting and/or transforming information.Operating on information may generally comprise relaying and/ortransmitting the information, e.g. on an air interface, which mayinclude mapping the information onto signaling (such mapping maygenerally pertain to one or more layers, e.g. one or more layers of anair interface, e.g. RLC (Radio Link Control) layer and/or MAC layerand/or physical layer/s). The information may be imprinted (or mapped)on communication signaling based on the target indication, which maymake it particularly suitable for use in a RAN (e.g., for a targetdevice like a network node or in particular a UE or terminal). The toolmay generally be adapted for use on a target device, like a UE orterminal. Generally, the tool may provide multiple functionalities, e.g.for providing and/or selecting the target indication, and/or presenting,e.g. video and/or audio, and/or operating on and/or storing receivedinformation. Providing a target indication may comprise transmitting ortransferring the indication as signaling, and/or carried on signaling,in a RAN, for example if the target device is a UE, or the tool for aUE. It should be noted that such provided information may be transferredto the information system via one or more additionally communicationinterfaces and/or paths and/or connections. The target indication may bea higher-layer indication and/or the information provided by theinformation system may be higher-layer information, e.g. applicationlayer or user-layer, in particular above radio layers like transportlayer and physical layer. The target indication may be mapped onphysical layer radio signaling, e.g. related to or on the user-plane,and/or the information may be mapped on physical layer radiocommunication signaling, e.g. related to or on the user-plane (inparticular, in reverse communication directions). The describedapproaches allow a target indication to be provided, facilitatinginformation to be provided in a specific format particularly suitableand/or adapted to efficiently use an air interface. A user input may forexample represent a selection from a plurality of possible transmissionmodes or formats, and/or paths, e.g. in terms of data rate and/orpackaging and/or size of information to be provided by the informationsystem.

In general, a numerology and/or subcarrier spacing may indicate thebandwidth (in frequency domain) of a subcarrier of a carrier, and/or thenumber of subcarriers in a carrier and/or the numbering of thesubcarriers in a carrier, and/or the symbol time length. Differentnumerologies may in particular be different in the bandwidth of asubcarrier. In some variants, all the subcarriers in a carrier have thesame bandwidth associated to them. The numerology and/or subcarrierspacing may be different between carriers in particular regarding thesubcarrier bandwidth. A symbol time length, and/or a time length of atiming structure pertaining to a carrier may be dependent on the carrierfrequency, and/or the subcarrier spacing and/or the numerology. Inparticular, different numerologies may have different symbol timelengths, even on the same carrier.

Signaling may generally comprise one or more (e.g., modulation) symbolsand/or signals and/or messages. A signal may comprise or represent oneor more bits. An indication may represent signaling, and/or beimplemented as a signal, or as a plurality of signals. One or moresignals may be included in and/or represented by a message. Signaling,in particular control signaling, may comprise a plurality of signalsand/or messages, which may be transmitted on different carriers and/orbe associated to different signaling processes, e.g. representing and/orpertaining to one or more such processes and/or correspondinginformation. An indication may comprise signaling, and/or a plurality ofsignals and/or messages and/or may be comprised therein, which may betransmitted on different carriers and/or be associated to differentacknowledgement signaling processes, e.g. representing and/or pertainingto one or more such processes. Signaling associated to a channel may betransmitted such that represents signaling and/or information for thatchannel, and/or that the signaling is interpreted by the transmitterand/or receiver to belong to that channel. Such signaling may generallycomply with transmission parameters and/or format/s for the channel.

An antenna arrangement may comprise one or more antenna elements(radiating elements), which may be combined in antenna arrays. Anantenna array or subarray may comprise one antenna element, or aplurality of antenna elements, which may be arranged e.g. twodimensionally (for example, a panel) or three dimensionally. It may beconsidered that each antenna array or subarray or element is separatelycontrollable, respectively that different antenna arrays arecontrollable separately from each other. A single antennaelement/radiator may be considered the smallest example of a subarray.Examples of antenna arrays comprise one or more multi-antenna panels orone or more individually controllable antenna elements. An antennaarrangement may comprise a plurality of antenna arrays. It may beconsidered that an antenna arrangement is associated to a (specificand/or single) radio node, e.g. a configuring or informing or schedulingradio node, e.g. to be controlled or controllable by the radio node. Anantenna arrangement associated to a UE or terminal may be smaller (e.g.,in size and/or number of antenna elements or arrays) than the antennaarrangement associated to a network node. Antenna elements of an antennaarrangement may be configurable for different arrays, e.g. to change thebeamforming characteristics. In particular, antenna arrays may be formedby combining one or more independently or separately controllableantenna elements or subarrays. The beams may be provided by analogbeamforming, or in some variants by digital beamforming, or by hybridbeamforming combing analog and digital beamforming. The informing radionodes may be configured with the manner of beam transmission, e.g. bytransmitting a corresponding indicator or indication, for example asbeam identify indication. However, there may be considered cases inwhich the informing radio node/s are not configured with suchinformation, and/or operate transparently, not knowing the way ofbeamforming used. An antenna arrangement may be considered separatelycontrollable in regard to the phase and/or amplitude/power and/or gainof a signal feed to it for transmission, and/or separately controllableantenna arrangements may comprise an independent or separate transmitand/or receive unit and/or ADC (Analog-Digital-Converter, alternativelyan ADC chain) or DCA (Digital-to-Analog Converter, alternatively a DCAchain) to convert digital control information into an analog antennafeed for the whole antenna arrangement (the ADC/DCA may be consideredpart of, and/or connected or connectable to, antenna circuitry) or viceversa. A scenario in which an ADC or DCA is controlled directly forbeamforming may be considered an analog beamforming scenario; suchcontrolling may be performed after encoding/decoding and 7or aftermodulation symbols have been mapped to resource elements. This may be onthe level of antenna arrangements using the same ADC/DCA, e.g. oneantenna element or a group of antenna elements associated to the sameADC/DCA. Digital beamforming may correspond to a scenario in whichprocessing for beamforming is provided before feeding signaling to theADC/DCA, e.g. by using one or more precoder/s and/or by precodinginformation, for example before and/or when mapping modulation symbolsto resource elements. Such a precoder for beamforming may provideweights, e.g. for amplitude and/or phase, and/or may be based on a(precoder) codebook, e.g. selected from a codebook. A precoder maypertain to one beam or more beams, e.g. defining the beam or beams. Thecodebook may be configured or configurable, and/or be predefined. DFTbeamforming may be considered a form of digital beamforming, wherein aDFT procedure is used to form one or more beams. Hybrid forms ofbeamforming may be considered.

A beam may be defined by a spatial and/or angular and/or spatial angulardistribution of radiation and/or a spatial angle (also referred to assolid angle) or spatial (solid) angle distribution into which radiationis transmitted (for transmission beamforming) or from which it isreceived (for reception beamforming). Reception beamforming may compriseonly accepting signals coming in from a reception beam (e.g., usinganalog beamforming to not receive outside reception beam/s), and/orsorting out signals that do not come in in a reception beam, e.g. indigital postprocessing, e.g. digital beamforming. A beam may have asolid angle equal to or smaller than 4*pi sr (4*pi correspond to a beamcovering all directions), in particular smaller than 2* pi, or pi, orpi/2, or pi/4 or pi/8 or pi/16. In particular for high frequencies,smaller beams may be used. Different beams may have different directionsand/or sizes (e.g., solid angle and/or reach). A beam may have a maindirection, which may be defined by a main lobe (e.g., center of the mainlobe, e.g. pertaining to signal strength and/or solid angle, which maybe averaged and/or weighted to determine the direction), and may haveone or more sidelobes. A lobe may generally be defined to have acontinuous or contiguous distribution of energy and/or power transmittedand/or received, e.g. bounded by one or more contiguous or contiguousregions of zero energy (or practically zero energy). A main lobe maycomprise the lobe with the largest signal strength and/or energy and/orpower content. However, sidelobes usually appear due to limitations ofbeamforming, some of which may carry signals with significant strength,and may cause multi-path effects. A sidelobe may generally have adifferent direction than a main lobe and/or other side lobes, however,due to reflections a sidelobe still may contribute to transmitted and/orreceived energy or power. A beam may be swept and/or switched over time,e.g., such that its (main) direction is changed, but its shape(angular/solid angle distribution) around the main direction is notchanged, e.g. from the transmitter's views for a transmission beam, orthe receiver's view for a reception beam, respectively. Sweeping maycorrespond to continuous or near continuous change of main direction(e.g., such that after each change, the main lobe from before the changecovers at least partly the main lobe after the change, e.g. at least to50 or 75 or 90 percent). Switching may correspond to switching directionnon-continuously, e.g. such that after each change, the main lobe frombefore the change does not cover the main lobe after the change, e.g. atmost to 50 or 25 or 10 percent.

In some cases, to one or more beams or signals or signalings may beassociated a Quasi-CoLocation (QCL) characteristic or set ofcharacteristics, or QCL class (also referred to as QCL type) or QCLidentity; beams or signal or signalings sharing such may be consideredto be Quasi-Colocated. Quasi-Colocated beams or signals or signalingsmay be considered (e.g., by a receiver) as the same beam or originatingfrom the same transmitter or transmission source, at least in regard tothe QCL characteristic or set or class or identity, and/or to share thecharacteristic/s. QCL characteristics may pertain to propagation ofsignaling, and/or one or more delay characteristics, and/or pathloss,and/or signal quality, and/or signal strength, and/or beam direction,and/or beam shape (in particular, angle or area, e.g. area of coverage),and/or Doppler shift, and/or Doppler spread, and/or delay spread, and/ortime synchronisation, and/or frequency synchronisation, and/or one ormore other parameters, e.g. pertaining to a propagation channel and/orspatial RX parameter/s (which may refer to reception beam and/ortransmission beam, e.g. shape or coverage or direction). A QCLcharacteristic may pertain to a specific channel (e.g., physical layerchannel like a control channel or data channel) and/or referencesignaling type and/or antenna port. Different QCL classes or types maypertain to different QCL characteristics or sets of characteristics; aQCL class may define and/or pertain to one or more criteria and/orthresholds and/or ranges for one or more QCL characteristics beams haveto fulfill to be considered Quasi-Colocated according to this class; aQCL identity may refer to and/or represent all beams beingquasi-colocated, according to a QCL class. Different classes may pertainto one or more of the same characteristics (e.g., different classes mayhave different criteria and/or thresholds and/or ranges for one or morecharacteristics) and/or to different characteristics. A QCL indicationmay be seen as a form of beam indication, e.g. pertaining to all beamsbelonging to one QCL class and/or QCL identity and/or quasi-colocatedbeams. A QCL identity may be indicated by a QCL indication. In somecases, a beam, and/or a beam indication, may be considered to referand/or represent a to a QCL identity, and/or to representquasi-colocated beams or signals or signalings. To a QCL identity, theremay be associated one or more ports, e.g. for one or more referencesignaling types, e.g. DM-RS and/or CSI-RS and/or PT-RS. A QCI class oridentity may be indicated by, and/or represented by, and/or beassociated to a Transmission Configuration Indicator (TCI), which may beindicated with control signaling, e.g. in a DCI.

Transmission on multiple layers (multi-layer transmission) may refer totransmission of communication signaling and/or reference signalingsimultaneously in one or more beams and/or using a plurality oftransmission sources, e.g. controlled by one network node or onewireless device. The layers may refer to layers of transmission; a layermay be considered to represent one data or signaling stream. Differentlayers may carry different data and/or data streams, e.g., to increasedata throughput. In some cases, the same data or data stream may betransported on different layers, e.g. to increase reliability.Multi-layer transmission may provide diversity, e.g. transmissiondiversity and/or spatial diversity. It may be considered thatmulti-layer transmission comprises 2, or more than 2 layers; the numberof layers of transmission may be represented by a rank or rankindication.

Signal strength may be a representation of signal power and/or signalenergy, e.g. as seen from a transmitting node or a receiving node. Abeam with larger strength at transmission (e.g., according to thebeamforming used) than another beam does may not necessarily have largerstrength at the receiver, and vice versa, for example due tointerference and/or obstruction and/or dispersion and/or absorptionand/or reflection and/or attrition or other effects influencing a beamor the signaling it carries. Signal quality may in general be arepresentation of how well a signal may be received over noise and/orinterference. A beam with better signal quality than another beam doesnot necessarily have a larger beam strength than the other beam. Signalquality may be represented for example by SIR, SNR, SINR, BER, BLER,Energy per resource element over noise/interference or anothercorresponding quality measure. Signal quality and/or signal strength maypertain to, and/or may be measured with respect to, a beam, and/orspecific signaling carried by the beam, e.g. reference signaling and/ora specific channel, e.g. a data channel or control channel. Signalstrength may be represented by received signal strength (e.g., as RSRP),and/or relative signal strength, e.g. in comparison to a referencesignal (strength), or Energy per resource element or a transmitterpower.

Uplink or sidelink signaling may be OFDMA (Orthogonal Frequency DivisionMultiple Access) or SC-FDMA (Single Carrier Frequency Division MultipleAccess) signaling. Downlink signaling may in particular be OFDMAsignaling. However, signaling is not limited thereto (Filter-Bank basedsignaling and/or Single-Carrier based signaling, e.g. SC-FDE signaling,may be considered alternatives).

A radio node may generally be considered a device or node adapted forwireless and/or radio (and/or millimeter wave) frequency communication,and/or for communication utilising an air interface, e.g. according to acommunication standard.

A radio node may be a network node, or a user equipment or terminal. Anetwork node may be any radio node of a wireless communication network,e.g. a base station and/or gNodeB (gNB) and/or eNodeB (eNB) and/or relaynode and/or micro/nano/pico/femto node and/or transmission point (TP)and/or access point (AP) and/or other node, in particular for a RAN orother wireless communication network as described herein.

The terms user equipment (UE) and terminal may be considered to beinterchangeable in the context of this disclosure. A wireless device,user equipment or terminal may represent an end device for communicationutilising the wireless communication network, and/or be implemented as auser equipment according to a standard. Examples of user equipments maycomprise a phone like a smartphone, a personal communication device, amobile phone or terminal, a computer, in particular laptop, a sensor ormachine with radio capability (and/or adapted for the air interface), inparticular for MTC (Machine-Type-Communication, sometimes also referredto M2M, Machine-To-Machine), or a vehicle adapted for wirelesscommunication. A user equipment or terminal may be mobile or stationary.A wireless device generally may comprise, and/or be implemented as,processing circuitry and/or radio circuitry, which may comprise one ormore chips or sets of chips. The circuitry and/or circuitries may bepackaged, e.g. in a chip housing, and/or may have one or more physicalinterfaces to interact with other circuitry and/or for power supply.Such a wireless device may be intended for use in a user equipment orterminal.

A radio node may generally comprise processing circuitry and/or radiocircuitry. A radio node, in particular a network node, may in some casescomprise cable circuitry and/or communication circuitry, with which itmay be connected or connectable to another radio node and/or a corenetwork.

Circuitry may comprise integrated circuitry. Processing circuitry maycomprise one or more processors and/or controllers (e.g.,microcontrollers), and/or ASICs (Application Specific IntegratedCircuitry) and/or FPGAs (Field Programmable Gate Array), or similar. Itmay be considered that processing circuitry comprises, and/or is(operatively) connected or connectable to one or more memories or memoryarrangements. A memory arrangement may comprise one or more memories. Amemory may be adapted to store digital information. Examples formemories comprise volatile and non-volatile memory, and/or Random AccessMemory (RAM), and/or Read-Only-Memory (ROM), and/or magnetic and/oroptical memory, and/or flash memory, and/or hard disk memory, and/orEPROM or EEPROM (Erasable Programmable ROM or Electrically ErasableProgrammable ROM).

Radio circuitry may comprise one or more transmitters and/or receiversand/or transceivers (a transceiver may operate or be operable astransmitter and receiver, and/or may comprise joint or separatedcircuitry for receiving and transmitting, e.g. in one package orhousing), and/or may comprise one or more amplifiers and/or oscillatorsand/or filters, and/or may comprise, and/or be connected or connectableto antenna circuitry and/or one or more antennas and/or antenna arrays.An antenna array may comprise one or more antennas, which may bearranged in a dimensional array, e.g. 2D or 3D array, and/or antennapanels. A remote radio head (RRH) may be considered as an example of anantenna array. However, in some variants, an RRH may be also beimplemented as a network node, depending on the kind of circuitry and/orfunctionality implemented therein.

Communication circuitry may comprise radio circuitry and/or cablecircuitry. Communication circuitry generally may comprise one or moreinterfaces, which may be air interface/s and/or cable interface/s and/oroptical interface/s, e.g. laser-based. Interface/s may be in particularpacket-based. Cable circuitry and/or a cable interfaces may comprise,and/or be connected or connectable to, one or more cables (e.g., opticalfiber-based and/or wire-based), which may be directly or indirectly(e.g., via one or more intermediate systems and/or interfaces) beconnected or connectable to a target, e.g. controlled by communicationcircuitry and/or processing circuitry.

Any one or any combination or all of modules disclosed herein may beimplemented in software and/or firmware and/or hardware. Differentmodules may be associated to different components of a radio node, e.g.different circuitries, or different parts of a circuitry. It may beconsidered that a module is distributed over different components and/orcircuitries. A program product as described herein may comprise themodules related to a device on which the program product is intended(e.g., a user equipment or network node) to be executed (the executionmay be performed on, and/or controlled by the associated circuitry).

A wireless communication network may be or comprise a radio accessnetwork and/or a backhaul network (e.g. a relay or backhaul network oran IAB network), and/or a Radio Access Network (RAN) in particularaccording to a communication standard. A communication standard may inparticular a standard according to 3 GPP and/or 5 G, e.g. according toNR or LTE, in particular LTE Evolution.

A wireless communication network may be and/or comprise a Radio AccessNetwork (RAN), which may be and/or comprise any kind of cellular and/orwireless radio network, which may be connected or connectable to a corenetwork. The approaches described herein are particularly suitable for a5 G network, e.g. LTE Evolution and/or NR (New Radio), respectivelysuccessors thereof. A RAN may comprise one or more network nodes, and/orone or more terminals, and/or one or more radio nodes. A network nodemay in particular be a radio node adapted for radio and/or wirelessand/or cellular communication with one or more terminals. A terminal maybe any device adapted for radio and/or wireless and/or cellularcommunication with or within a RAN, e.g. a user equipment (UE) or mobilephone or smartphone or computing device or vehicular communicationdevice or device for machine-type-communication (MTC), etc. A terminalmay be mobile, or in some cases stationary. A RAN or a wirelesscommunication network may comprise at least one network node and a UE,or at least two radio nodes. There may be generally considered awireless communication network or system, e.g. a RAN or RAN system,comprising at least one radio node, and/or at least one network node andat least one terminal.

Transmitting in downlink may pertain to transmission from the network ornetwork node to the terminal. Transmitting in uplink may pertain totransmission from the terminal to the network or network node.Transmitting in sidelink may pertain to (direct) transmission from oneterminal to another. Uplink, downlink and sidelink (e.g., sidelinktransmission and reception) may be considered communication directions.In some variants, uplink and downlink may also be used to describedwireless communication between network nodes, e.g. for wireless backhauland/or relay communication and/or (wireless) network communication forexample between base stations or similar network nodes, in particularcommunication terminating at such. It may be considered that backhauland/or relay communication and/or network communication is implementedas a form of sidelink or uplink communication or similar thereto.

Control information or a control information message or correspondingsignaling (control signaling) may be transmitted on a control channel,e.g. a physical control channel, which may be a downlink channel or (ora sidelink channel in some cases, e.g. one UE scheduling another UE).For example, control information/allocation information may be signaledby a network node on PDCCH (Physical Downlink Control Channel) and/or aPDSCH (Physical Downlink Shared Channel) and/or a HARQ-specific channel.Acknowledgement signaling, e.g. as a form of control information orsignaling like uplink control information/signaling, may be transmittedby a terminal on a PUCCH (Physical Uplink Control Channel) and/or PUSCH(Physical Uplink Shared Channel) and/or a HARQ-specific channel.Multiple channels may apply for multi-component/multi-carrier indicationor signaling.

Scheduling may comprise indicating, e.g. with control signaling like DCIor SCI signaling and/or signaling on a control channel like PDCCH orPSCCH, one or more scheduling opportunities of a configuration intendedto carry data signaling or subject signaling. The configuration may berepresented or representable by, and/or correspond to, a table. Ascheduling assignment may for example point to an opportunity of thereception allocation configuration, e.g. indexing a table of schedulingopportunities. In some cases, a reception allocation configuration maycomprise 15 or 16 scheduling opportunities. The configuration may inparticular represent allocation in time. It may be considered that thereception allocation configuration pertains to data signaling, inparticular on a physical data channel like PDSCH or PSSCH. In general,the reception allocation configuration may pertain to downlinksignaling, or in some scenarios to sidelink signaling. Control signalingscheduling subject transmission like data signaling may point and/orindex and/or refer to and/or indicate a scheduling opportunity of thereception allocation configuration. It may be considered that thereception allocation configuration is configured or configurable withhigher-layer signaling, e.g. RRC or MAC layer signaling. The receptionallocation configuration may be applied and/or applicable and/or validfor a plurality of transmission timing intervals, e.g. such that foreach interval, one or more opportunities may be indicated or allocatedfor data signaling. These approaches allow efficient and flexiblescheduling, which may be semi-static, but may updated or reconfigured onuseful timescales in response to changes of operation conditions.

Signaling may generally be considered to represent an electromagneticwave structure (e.g., over a time interval and frequency interval),which is intended to convey information to at least one specific orgeneric (e.g., anyone who might pick up the signaling) target. A processof signaling may comprise transmitting the signaling. Transmittingsignaling, in particular control signaling or communication signaling,e.g. comprising, or representing acknowledgement signaling and/orresource requesting information, may comprise encoding and/ormodulating. Encoding and/or modulating may comprise error detectioncoding and/or forward error correction encoding and/or scrambling.Receiving signaling like control signaling or data signaling maycomprise corresponding decoding and/or demodulation, e.g. based onreference signaling associated to the signaling to be received. Errordetection coding may comprise, and/or be based on, parity or checksumapproaches, e.g. CRC (Cyclic Redundancy Check). Forward error correctioncoding may comprise and/or be based on for example turbo coding and/orReed-Muller coding, and/or polar coding and/or LDPC coding (Low DensityParity Check). The type of coding used may be based on the channel(e.g., physical channel) the coded signal is associated to. A code ratemay represent the ratio of the number of information bits beforeencoding to the number of encoded bits after encoding, considering thatencoding adds coding bits for error detection coding and forward errorcorrection. Coded bits may refer to information bits (also calledsystematic bits) plus coding bits.

Communication signaling may comprise, and/or represent, and/or beimplemented as, data signaling, and/or user plane signaling.Communication signaling may be associated to a data channel, e.g. aphysical downlink channel or physical uplink channel or physicalsidelink channel, in particular a PDSCH (Physical Downlink SharedChannel) or PSSCH (Physical Sidelink Shared Channel). Generally, a datachannel may be a shared channel or a dedicated channel. Data signalingmay be signaling associated to and/or on a data channel.

An indication generally may explicitly and/or implicitly indicate theinformation it represents and/or indicates. Implicit indication may forexample be based on position and/or resource used for transmission.Explicit indication may for example be based on a parametrisation withone or more parameters, and/or one or more index or indices, and/or oneor more bit patterns representing the information. It may in particularbe considered that control signaling as described herein, based on theutilised resource sequence, implicitly indicates the control signalingtype.

A resource element may generally describe the smallest individuallyusable and/or encodable and/or decodable and/or modulatable and/ordemodulatable time-frequency resource, and/or may describe atime-frequency resource covering a symbol time length in time and asubcarrier in frequency. A signal may be allocatable and/or allocated toa resource element. A subcarrier may be a subband of a carrier, e.g. asdefined by a standard. A carrier may define a frequency and/or frequencyband for transmission and/or reception. In some variants, a signal(jointly encoded/modulated) may cover more than one resource elements. Aresource element may generally be as defined by a correspondingstandard, e.g. NR or LTE. As symbol time length and/or subcarrierspacing (and/or numerology) may be different between different symbolsand/or subcarriers, different resource elements may have differentextension (length/width) in time and/or frequency domain, in particularresource elements pertaining to different carriers.

A resource generally may represent a time-frequency and/or coderesource, on which signaling, e.g. according to a specific format, maybe communicated, for example transmitted and/or received, and/or beintended for transmission and/or reception.

A border symbol (or allocation unit) may generally represent a startingsymbol (allocation unit) or an ending symbol (allocation unit) fortransmitting and/or receiving. A starting symbol (or allocation unit)may in particular be a starting symbol of uplink or sidelink signaling,for example control signaling or data signaling. Such signaling may beon a data channel or control channel, e.g. a physical channel, inparticular a physical uplink shared channel (like PUSCH) or a sidelinkdata or shared channel, or a physical uplink control channel (likePUCCH) or a sidelink control channel. If the starting symbol (orallocation unit) is associated to control signaling (e.g., on a controlchannel), the control signaling may be in response to received signaling(in sidelink or downlink), e.g. representing acknowledgement signalingassociated thereto, which may be HARQ or ARQ signaling. An ending symbol(or allocation unit) may represent an ending symbol (in time) ofdownlink or sidelink transmission or signaling, which may be intended orscheduled for the radio node or user equipment. Such downlink signalingmay in particular be data signaling, e.g. on a physical downlink channellike a shared channel, e.g. a PDSCH (Physical Downlink Shared Channel).A starting symbol (or allocation unit) may be determined based on,and/or in relation to, such an ending symbol (or allocation unit).

Configuring a radio node, in particular a terminal or user equipment,may refer to the radio node being adapted or caused or set and/orinstructed to operate according to the configuration. Configuring may bedone by another device, e.g., a network node (for example, a radio nodeof the network like a base station or eNodeB) or network, in which caseit may comprise transmitting configuration data to the radio node to beconfigured. Such configuration data may represent the configuration tobe configured and/or comprise one or more instruction pertaining to aconfiguration, e.g. a configuration for transmitting and/or receiving onallocated resources, in particular frequency resources. A radio node mayconfigure itself, e.g., based on configuration data received from anetwork or network node. A network node may utilise, and/or be adaptedto utilise, its circuitry/ies for configuring. Allocation informationmay be considered a form of configuration data. Configuration data maycomprise and/or be represented by configuration information, and/or oneor more corresponding indications and/or message/s

Generally, configuring may include determining configuration datarepresenting the configuration and providing, e.g. transmitting, it toone or more other nodes (parallel and/or sequentially), which maytransmit it further to the radio node (or another node, which may berepeated until it reaches the wireless device). Alternatively, oradditionally, configuring a radio node, e.g., by a network node or otherdevice, may include receiving configuration data and/or data pertainingto configuration data, e.g., from another node like a network node,which may be a higher-level node of the network, and/or transmittingreceived configuration data to the radio node. Accordingly, determininga configuration and transmitting the configuration data to the radionode may be performed by different network nodes or entities, which maybe able to communicate via a suitable interface, e.g., an X2 interfacein the case of LTE or a corresponding interface for NR. Configuring aterminal may comprise scheduling downlink and/or uplink transmissionsfor the terminal, e.g. downlink data and/or downlink control signalingand/or DCI and/or uplink control or data or communication signaling, inparticular acknowledgement signaling, and/or configuring resourcesand/or a resource pool therefor.

A resource structure may be considered to be neighbored in frequencydomain by another resource structure, if they share a common borderfrequency, e.g. one as an upper frequency border and the other as alower frequency border. Such a border may for example be represented bythe upper end of a bandwidth assigned to a subcarrier n, which alsorepresents the lower end of a bandwidth assigned to a subcarrier n+1. Aresource structure may be considered to be neighbored in time domain byanother resource structure, if they share a common border time, e.g. oneas an upper (or right in the figures) border and the other as a lower(or left in the figures) border. Such a border may for example berepresented by the end of the symbol time interval assigned to a symboln, which also represents the beginning of a symbol time intervalassigned to a symbol n+1.

Generally, a resource structure being neighbored by another resourcestructure in a domain may also be referred to as abutting and/orbordering the other resource structure in the domain.

A resource structure may in general represent a structure in time and/orfrequency domain, in particular representing a time interval and afrequency interval. A resource structure may comprise and/or becomprised of resource elements, and/or the time interval of a resourcestructure may comprise and/or be comprised of symbol time interval/s,and/or the frequency interval of a resource structure may compriseand/or be comprised of subcarrier/s. A resource element may beconsidered an example for a resource structure, a slot or mini-slot or aPhysical Resource Block (PRB) or parts thereof may be considered others.A resource structure may be associated to a specific channel, e.g. aPUSCH or PUCCH, in particular resource structure smaller than a slot orPRB.

Examples of a resource structure in frequency domain comprise abandwidth or band, or a bandwidth part. A bandwidth part may be a partof a bandwidth available for a radio node for communicating, e.g. due tocircuitry and/or configuration and/or regulations and/or a standard. Abandwidth part may be configured or configurable to a radio node. Insome variants, a bandwidth part may be the part of a bandwidth used forcommunicating, e.g. transmitting and/or receiving, by a radio node. Thebandwidth part may be smaller than the bandwidth (which may be a devicebandwidth defined by the circuitry/configuration of a device, and/or asystem bandwidth, e.g. available for a RAN). It may be considered that abandwidth part comprises one or more resource blocks or resource blockgroups, in particular one or more PRBs or PRB groups. A bandwidth partmay pertain to, and/or comprise, one or more carriers. A resourcestructure may in time domain comprise and/or represent a time interval,e.g. one of more allocation units and/or symbols and/or slots and/orsubframes. In general, any reference to a symbol as a time interval maybe considered as a reference to an allocation unit as a more generalterm, unless the reference to the symbol is specific, e.g. referring toa specific division or modulation technique, or to modulation symbols astransmission structures.

A carrier may generally represent a frequency range or band and/orpertain to a central frequency and an associated frequency interval. Itmay be considered that a carrier comprises a plurality of subcarriers. Acarrier may have assigned to it a central frequency or center frequencyinterval, e.g. represented by one or more subcarriers (to eachsubcarrier there may be generally assigned a frequency bandwidth orinterval). Different carriers may be non-overlapping, and/or may beneighboring in frequency domain.

It should be noted that the term “radio” in this disclosure may beconsidered to pertain to wireless communication in general, and may alsoinclude wireless communication utilising millimeter waves, in particularabove one of the thresholds 10 GHz or 20 GHz or 50 GHz or 52 GHz or 52.6GHz or 60 GHz or 72 GHz or 100 GHz or 114 GHz. Such communication mayutilise one or more carriers, e.g. in FDD and/or carrier aggregation.Upper frequency boundaries may correspond to 300 GHz or 200 GHz or 120GHz or any of the thresholds larger than the one representing the lowerfrequency boundary.

A radio node, in particular a network node or a terminal, may generallybe any device adapted for transmitting and/or receiving radio and/orwireless signals and/or data, in particular communication data, inparticular on at least one carrier. The at least one carrier maycomprise a carrier accessed based on an LBT procedure (which may becalled LBT carrier), e.g., an unlicensed carrier. It may be consideredthat the carrier is part of a carrier aggregate.

Receiving or transmitting on a cell or carrier may refer to receiving ortransmitting utilizing a frequency (band) or spectrum associated to thecell or carrier. A cell may generally comprise and/or be defined by orfor one or more carriers, in particular at least one carrier for ULcommunication/transmission (called UL carrier) and at least one carrierfor DL communication/transmission (called DL carrier). It may beconsidered that a cell comprises different numbers of UL carriers and DLcarriers. Alternatively, or additionally, a cell may comprise at leastone carrier for UL communication/transmission and DLcommunication/transmission, e.g., in TDD-based approaches.

A channel may generally be a logical, transport or physical channel. Achannel may comprise and/or be arranged on one or more carriers, inparticular a plurality of subcarriers. A channel carrying and/or forcarrying control signaling/control information may be considered acontrol channel, in particular if it is a physical layer channel and/orif it carries control plane information. Analogously, a channel carryingand/or for carrying data signaling/user information may be considered adata channel, in particular if it is a physical layer channel and/or ifit carries user plane information. A channel may be defined for aspecific communication direction, or for two complementary communicationdirections (e.g., UL and DL, or sidelink in two directions), in whichcase it may be considered to have two component channels, one for eachdirection. Examples of channels comprise a channel for low latencyand/or high reliability transmission, in particular a channel forUltra-Reliable Low Latency Communication (URLLC), which may be forcontrol and/or data.

In general, a symbol may represent and/or be associated to a symbol timelength, which may be dependent on the carrier and/or subcarrier spacingand/or numerology of the associated carrier. Accordingly, a symbol maybe considered to indicate a time interval having a symbol time length inrelation to frequency domain. A symbol time length may be dependent on acarrier frequency and/or bandwidth and/or numerology and/or subcarrierspacing of, or associated to, a symbol. Accordingly, different symbolsmay have different symbol time lengths. In particular, numerologies withdifferent subcarrier spacings may have different symbol time length.Generally, a symbol time length may be based on, and/or include, a guardtime interval or cyclic extension, e.g. prefix or postfix.

A sidelink may generally represent a communication channel (or channelstructure) between two UEs and/or terminals, in which data istransmitted between the participants (UEs and/or terminals) via thecommunication channel, e.g. directly and/or without being relayed via anetwork node. A sidelink may be established only and/or directly via airinterface/s of the participant, which may be directly linked via thesidelink communication channel. In some variants, sidelink communicationmay be performed without interaction by a network node, e.g. on fixedlydefined resources and/or on resources negotiated between theparticipants. Alternatively, or additionally, it may be considered thata network node provides some control functionality, e.g. by configuringresources, in particular one or more resource pool/s, for sidelinkcommunication, and/or monitoring a sidelink, e.g. for charging purposes.

Sidelink communication may also be referred to as device-to-device (D2D)communication, and/or in some cases as ProSe (Proximity Services)communication, e.g. in the context of LTE. A sidelink may be implementedin the context of V2x communication (Vehicular communication), e.g. V2V(Vehicle-to-Vehicle), V2I (Vehicle-to-Infrastructure) and/or V2P(Vehicle-to-Person). Any device adapted for sidelink communication maybe considered a user equipment or terminal.

A sidelink communication channel (or structure) may comprise one or more(e.g., physical or logical) channels, e.g. a PSCCH (Physical SidelinkControl CHannel, which may for example carry control information like anacknowledgement position indication, and/or a PSSCH (Physical SidelinkShared CHannel, which for example may carry data and/or acknowledgementsignaling). It may be considered that a sidelink communication channel(or structure) pertains to and/or used one or more carrier/s and/orfrequency range/s associated to, and/or being used by, cellularcommunication, e.g. according to a specific license and/or standard.Participants may share a (physical) channel and/or resources, inparticular in frequency domain and/or related to a frequency resourcelike a carrier) of a sidelink, such that two or more participantstransmit thereon, e.g. simultaneously, and/or time-shifted, and/or theremay be associated specific channels and/or resources to specificparticipants, so that for example only one participant transmits on aspecific channel or on a specific resource or specific resources, e.g.,in frequency domain and/or related to one or more carriers orsubcarriers.

A sidelink may comply with, and/or be implemented according to, aspecific standard, e.g. an LTE-based standard and/or NR. A sidelink mayutilise TDD (Time Division Duplex) and/or FDD (Frequency DivisionDuplex) technology, e.g. as configured by a network node, and/orpreconfigured and/or negotiated between the participants. A userequipment may be considered to be adapted for sidelink communication ifit, and/or its radio circuitry and/or processing circuitry, is adaptedfor utilising a sidelink, e.g. on one or more frequency ranges and/orcarriers and/or in one or more formats, in particular according to aspecific standard. It may be generally considered that a Radio AccessNetwork is defined by two participants of a sidelink communication.Alternatively, or additionally, a Radio Access Network may berepresented, and/or defined with, and/or be related to a network nodeand/or communication with such a node.

Communication or communicating may generally comprise transmittingand/or receiving signaling. Communication on a sidelink (or sidelinksignaling) may comprise utilising the sidelink for communication(respectively, for signaling). Sidelink transmission and/or transmittingon a sidelink may be considered to comprise transmission utilising thesidelink, e.g. associated resources and/or transmission formats and/orcircuitry and/or the air interface. Sidelink reception and/or receivingon a sidelink may be considered to comprise reception utilising thesidelink, e.g. associated resources and/or transmission formats and/orcircuitry and/or the air interface. Sidelink control information (e.g.,SCI) may generally be considered to comprise control informationtransmitted utilising a sidelink.

A transmission may generally pertain to a specific channel and/orspecific resources, in particular with a starting symbol and endingsymbol in time, covering the interval therebetween. A scheduledtransmission may be a transmission scheduled and/or expected and/or forwhich resources are scheduled or provided or reserved. However, notevery scheduled transmission has to be realized. For example, ascheduled downlink transmission may not be received, or a scheduleduplink transmission may not be transmitted due to power limitations, orother influences (e.g., a channel on an unlicensed carrier beingoccupied). A transmission may be scheduled for a transmission timingsubstructure (e.g., a mini-slot, and/or covering only a part of atransmission timing structure) within a transmission timing structurelike a slot. A border symbol may be indicative of a symbol in thetransmission timing structure at which the transmission starts or ends.

Predefined in the context of this disclosure may refer to the relatedinformation being defined for example in a standard, and/or beingavailable without specific configuration from a network or network node,e.g. stored in memory, for example independent of being configured.Configured or configurable may be considered to pertain to thecorresponding information being set/configured, e.g. by the network or anetwork node.

A configuration or schedule, like a mini-slot configuration and/orstructure configuration, may schedule transmissions, e.g. for thetime/transmissions it is valid, and/or transmissions may be scheduled byseparate signaling or separate configuration, e.g. separate RRCsignaling and/or downlink control information signaling. Thetransmission/s scheduled may represent signaling to be transmitted bythe device for which it is scheduled, or signaling to be received by thedevice for which it is scheduled, depending on which side of acommunication the device is. It should be noted that downlink controlinformation or specifically DCI signaling may be considered physicallayer signaling, in contrast to higher layer signaling like MAC (MediumAccess Control) signaling or RRC layer signaling. The higher the layerof signaling is, the less frequent/the more time/resource consuming itmay be considered, at least partially due to the information containedin such signaling having to be passed on through several layers, eachlayer requiring processing and handling.

A scheduled transmission, and/or transmission timing structure like amini-slot or slot, may pertain to a specific channel, in particular aphysical uplink shared channel, a physical uplink control channel, or aphysical downlink shared channel, e.g. PUSCH, PUCCH or PDSCH, and/or maypertain to a specific cell and/or carrier aggregation. A correspondingconfiguration, e.g. scheduling configuration or symbol configuration maypertain to such channel, cell and/or carrier aggregation. It may beconsidered that the scheduled transmission represents transmission on aphysical channel, in particular a shared physical channel, for example aphysical uplink shared channel or physical downlink shared channel. Forsuch channels, semi-persistent configuring may be particularly suitable.

Generally, a configuration may be a configuration indicating timing,and/or be represented or configured with corresponding configurationdata. A configuration may be embedded in, and/or comprised in, a messageor configuration or corresponding data, which may indicate and/orschedule resources, in particular semi-persistently and/orsemi-statically.

A control region of a transmission timing structure may be an intervalin time and/or frequency domain for intended or scheduled or reservedfor control signaling, in particular downlink control signaling, and/orfor a specific control channel, e.g. a physical downlink control channellike PDCCH. The interval may comprise, and/or consist of, a number ofsymbols in time, which may be configured or configurable, e.g. by(UE-specific) dedicated signaling (which may be single-cast, for exampleaddressed to or intended for a specific UE), e.g. on a PDCCH, or RRCsignaling, or on a multicast or broadcast channel. In general, thetransmission timing structure may comprise a control region covering aconfigurable number of symbols. It may be considered that in general theborder symbol is configured to be after the control region in time. Acontrol region may be associated, e.g. via configuration and/ordetermination, to one or more specific UEs and/or formats of PDCCHand/or DCI and/or identifiers, e.g. UE identifiers and/or RNTIs orcarrier/cell identifiers, and/or be represented and/or associated to aCORESET and/or a search space.

The duration of a symbol (symbol time length or interval or allocationunit) of the transmission timing structure may generally be dependent ona numerology and/or carrier, wherein the numerology and/or carrier maybe configurable. The numerology may be the numerology to be used for thescheduled transmission.

A transmission timing structure may comprise a plurality of allocationunits or symbols, and/or define an interval comprising several symbolsor allocation units (respectively their associated time intervals). Inthe context of this disclosure, it should be noted that a reference to asymbol for ease of reference may be interpreted to refer to the timedomain projection or time interval or time component or duration orlength in time of the symbol, unless it is clear from the context thatthe frequency domain component also has to be considered. Examples oftransmission timing structures include slot, subframe, mini-slot (whichalso may be considered a substructure of a slot), slot aggregation(which may comprise a plurality of slots and may be considered asuperstructure of a slot), respectively their time domain component. Atransmission timing structure may generally comprise a plurality ofsymbols and/or allocation units defining the time domain extension(e.g., interval or length or duration) of the transmission timingstructure, and arranged neighboring to each other in a numberedsequence. A timing structure (which may also be considered orimplemented as synchronisation structure) may be defined by a successionof such transmission timing structures, which may for example define atiming grid with symbols representing the smallest grid structures. Atransmission timing structure, and/or a border symbol or a scheduledtransmission may be determined or scheduled in relation to such a timinggrid. A transmission timing structure of reception may be thetransmission timing structure in which the scheduling control signalingis received, e.g. in relation to the timing grid. A transmission timingstructure may in particular be a slot or subframe or in some cases, amini-slot. In some cases, a timing structure may be represented by aframe structure. Timing structures may be associated to specifictransmitters and/or cells and/or beams and/or signalings.

Signaling utilising, and/or on and/or associated to, resources or aresource structure may be signaling covering the resources or structure,signaling on the associated frequency/ies and/or in the associated timeinterval/s. It may be considered that a signaling resource structurecomprises and/or encompasses one or more substructures, which may beassociated to one or more different channels and/or types of signalingand/or comprise one or more holes (resource element/s not scheduled fortransmissions or reception of transmissions). A resource substructure,e.g. a feedback resource structure, may generally be continuous in timeand/or frequency, within the associated intervals. It may be consideredthat a substructure, in particular a feedback resource structure,represents a rectangle filled with one or more resource elements intime/frequency space. However, in some cases, a resource structure orsubstructure, in particular a frequency resource range, may represent anon-continuous pattern of resources in one or more domains, e.g. timeand/or frequency. The resource elements of a substructure may bescheduled for associated signaling.

Example types of signaling comprise signaling of a specificcommunication direction, in particular, uplink signaling, downlinksignaling, sidelink signaling, as well as reference signaling (e.g., SRSor CRS or CSI-RS), communication signaling, control signaling, and/orsignaling associated to a specific channel like PUSCH, PDSCH, PUCCH,PDCCH, PSCCH, PSSCH, etc.).

A signaling sequence may correspond to a sequence of modulation symbols(e.g., in time domain, or in frequency domain for an OFDM system). Thesignaling sequence may be predefined, or configured or configurable,e.g. to a wireless device. For OFDM or SC-FDM, each element of asignaling sequence may be mapped to a subcarrier; in general, forSC-based signaling, a corresponding mapping in time domain may beutilised (for example, such that each element may use essentially thefull synchronisation bandwidth). A signaling sequence may comprise(ordered) modulation symbols, each modulation symbol representing avalue of the sequence it is based on, e.g. based on the modulationscheme used and/or in a phase or constellation diagram; for somesequences like Zadoff-Chu sequences, there may be a mapping betweennon-integer sequence elements and transmitted waveform, which may not berepresented in the context of a modulation scheme like BPSK or QPSK orhigher. A signaling sequence may be a physical layer signaling orsignal, which may be devoid of higher layer information. A signalingsequence may be based on a sequence, e.g. a bit sequence or symbolsequence and/or a modulation, e.g. performed on the sequence. Elementsof a signaling sequence may be mapped to frequency domain (e.g., tosubcarriers, in particular in a pattern like a comb structure or ininterlaces) and/or in time domain, e.g. to one or more allocation unitsor symbol time intervals. A DFT-s-OFDM based waveform may be a waveformconstructed by performing a DFT-spreading operation on modulationsymbols mapped to a frequency interval (e.g., subcarriers), e.g. toprovide a time-variable signal. A DFT-s-OFDM based waveform may also bereferred to a SC-FDM waveform. It may be considered to provide good PAPRcharacteristics, allowing optimised operation of power amplifiers, inparticular for high frequencies. In general, the approaches describedherein may also be applicable to Single-Carrier based waveforms, e.g.FDE-based waveforms. Communication, e.g. on data channel/s and/orcontrol channel/s, may be based on, and/o utilise, a DFT-s-OFDM basedwaveform, or a Single-Carrier based waveform.

A sequence may generally be considered to be based on a root sequence ifit can be constructed from the root sequence (or represents itdirectly), e.g. by shifting in phase and/or frequency and/or timedomain, and/or performing a cyclic shift and/or a cyclic extension,and/or copying/repeating and/or processing or operating on with a code,and/or interleaving or re-ordering of elements of the sequence, and/orextending or shortening the root sequence. A cyclic extension of asequence may comprise taking a part of the sequence (in particular aborder part like a tail or beginning) and appending it to the sequence,e.g. at the beginning or end, for example in time domain or frequencydomain. Thus, a cyclic extended sequence may represent a (root) sequenceand at least a part repetition of the (root) sequence. Operationsdescribed may be combined, in any order, in particular a shift and acyclic extension. A cyclic shift in a domain may comprise shifting thesequence in the domain within an interval, such that the total number ofsequence elements is constant, and the sequence is shifted as if theinterval represented a ring (e.g., such that starting from the samesequence element, which may appear at different location in theinterval), the order of elements is the same if the borders of theintervals are considered to be continuous, such that leaving one end ofthe interval leads to entering the interval at the other end).Processing and/or operating on with a code may correspond toconstructing a sequence out of copies of a root sequence, wherein eachcopy is multiplied and/or operated on with an element of the code.Multiplying with an element of a code may represent and/or correspond toa shift (e.g., constant, or linear or cyclic) in phase and/or frequencyand/or time domain, depending on representation. In the context of thisdisclosure, a sequence being based on and/or being constructed and/orprocessed may be any sequence that would result from such constructionor processing, even if the sequence is just read from memory. Anyisomorphic or equivalent or corresponding way to arrive at the sequenceis considered to be included by such terminology; the construction thusmay be considered to define the characteristics of the sequence and/orthe sequence, not necessarily a specific way to construct them, as theremay be multiple equivalent ways that are mathematically equivalent.Thus, a sequence “based on” or “constructed” or similar terminology maybe considered to correspond to the sequence being “represented by” or“may be represented by” or “representable as”.

A root sequence for a signaling sequence associated to one allocationunit may be basis for construction of a larger sequence. In this case,the larger sequence and/or the root sequence basis for its constructionmay be considered root sequence for signaling sequences associated toother allocation units.

For OFDM or SC-FDM, each element of a signaling sequence may be mappedto a subcarrier; in general, for SC-based signaling, a correspondingmapping in time domain may be utilised (such that each element may useessentially the full synchronisation bandwidth). A signaling sequencemay comprise (ordered) modulation symbols, each modulation symbolrepresenting a value of the sequence it is based on, e.g. based on themodulation scheme used and/or in a phase or constellation diagram; forsome sequences like Zadoff-Chu sequences, there may be a mapping betweennon-integer sequence elements and transmitted waveform, which may not berepresented in the context of a modulation scheme like BPSK or QPSK orhigher.

A signaling sequence of an allocation unit may be based on a sequenceroot, e.g. a root sequence. A sequence root in general may represent orindicate a base for deriving or determining a signaling sequence; theroot may be associated to, and/or represent a sequence directly, and/orindicate or represent a base sequence and/or seed. Examples of sequenceroots may comprise a Zadoff Chu root sequence, a sequence seed, e.g. aseed for a Gold sequence, or a Golay complimentary sequence. A signalingsequence may be derived or derivable from, and/or be based on, asequency root, e.g. based on a code, which may represent a shift oroperation or processing on the root sequence or a sequence indicated bythe sequence root, e.g. to provide the signaling sequence; the signalingsequence may be based on such shifted or processed or operated on rootsequence. The code may in particular represent a cyclic shift and/orphase shift and/or phase ramp (e.g., an amount for such). The code mayassign one operation or shift for each allocation unit.

In general, a signaling sequence associated to an allocation unit(and/or the allocation units) associated to control signaling (and/orreference signaling) may be based on a root sequence which may be aM-sequence or Zadoff-Chu sequence, or a Gold or Golay sequence, oranother sequence with suitable characteristics regarding correlationand/or interference (e.g., self-interference and/or interference withother or neighboring transmitters). Different sequences may be used asroot sequences for different signaling sequences, or the same sequencemay be used. If different sequences are used, they may be of the sametype (Gold, Golay, M- or Zadoff-Chu, for example). The (signaling and/orroot) sequences may correspond to or be time-domain sequences, e.g. timedomain Zadoff-Chu and/or time-domain M sequences.

In some cases, a shifted object like a signaling or signals or sequencesor information may be shifted, e.g. relative to a predecessor (e.g., oneis subject to a shift, and the shifted version is used), or relative toanother (e.g., one associated to one signaling or allocation unit may beshifted to another associated to a second signaling or allocation unit,both may be used). One possible way of shifting is operating a code onit, e.g. to multiply each element of a shifting object with a factor. Aramping (e.g. multiplying with a monotonously increasing or periodicfactor) may be considered an example of shifting. Another is a cyclicshift in a domain or interval. A cyclic shift (or circular shift) maycorrespond to a rearrangement of the elements in the shifting object,corresponding to moving the final element or elements to the firstposition, while shifting all other entries to the next position, or byperforming the inverse operation (such that the shifted object as theresult will have the same elements as the shifting object, in a shiftedbut similar order). Shifting in general may be specific to an intervalin a domain, e.g. an allocation unit in time domain, or a bandwidth infrequency domain. For example, it may be considered that signals ormodulation symbols in an allocation unit are shifted, such that theorder of the modulation symbols or signals is shifted in the allocationunit. In another example, allocation units may be shifted, e.g. in alarger time interval—this may leave signals in the allocation unitsunshifted with reference to the individual allocation unit, but maychange the order of the allocation units. Domains for shifting may forexample be time domain and/or phase domain and/or frequency domain.Multiple shifts in the same domain or different domains, and/or the sameinterval or different intervals (differently sized intervals, forexample) may be performed.

Reference signaling may have a type. Types of reference signaling mayinclude synchronisation signaling, and/or DM-RS (used to facilitatedemodulation of associated data signaling and/or control signaling),and/or PT-RS (used to facilitate phase tracking of associated datasignaling and/or control signaling, e.g. within a time interval orsymbol or allocation unit carrying such signaling), and/or CSI-RS (e.g.,used for channel estimation and/or reporting). It may be considered thatPT-RS are inserted into a bit sequence, or a modulation symbol sequence,which may represent data. For example, PT-RS may be mapped ontosubcarriers of a symbol also carrying data symbols. Accordingly, PT-RSinsertion may be optimised for hardware implementations. In some cases,PT-RS may be modulated differently and/or independently of themodulation symbols representing data (or data bits).

A comb structure, or short comb, may indicate a distribution, orperiodic arrangement of reference signaling, in particular in frequencyspace, e.g. between an upper and lower frequency. A comb may pertain toone FDMA symbol and/or one (the same) symbol time interval or allocationunit. A comb may have width or size N and/or may pertain to, and/or beassociated to, specific signaling and/or a type of signaling, e.g. atype of reference signaling. The width N may indicate how many emptysubcarriers are between (e.g., non-neighbouring) subcarriers carrying anelement or signal or symbol of the signaling (e.g., this number may beN-1), or how many empty subcarriers and non-empty subcarriers form apattern that is repeated in frequency domain. In general, each comb mayindicate that at least one empty subcarrier is to be between non-emptysubcarriers. In this context, empty may refer to empty regarding thepattern or distribution of the signaling associated to the comb (andnon-empty may refer to a subcarrier carrying an element or symbol of theassociated signaling); in some cases, other signalings (which may have acomb structure as well) may be carried on empty subcarriers, e.g.transmitted using other transmission sources and/or other devices,and/or mapped into the comb (e.g., for a DMRS comb, data signaling maybe mapped on subcarriers not carrying DMRS). A comb structure maygenerally describe a structure in which for every N-th (N may be aninteger) resource element and/or subcarrier a reference signal or anelement of a sequence of the reference signaling, and/or representingthe reference signaling, and/or on which the reference signaling isbased, is mapped to, and/or represented by signaling the resourceelement and/or subcarrier, in particular an element (symbol) of amodulation symbol sequence, or an element of a sequence. N may be calledthe width of the comb. Generally, the comb may indicate the periodicityof the pattern inside the frequency range of the reference signaling.The pattern may in particular pertain to one reference signal and/orresource element or subcarrier for transmitting a reference signal, suchthat the comb may be considered to indicate that on every N-th resourceelement (in particular, only there) and/or subcarrier there is to be areference signal or element of an associated sequence, and/or how manyresource elements and/or subcarriers are between resource elementsand/or subcarriers with reference signals. However, there may beconsidered variants, in which the pattern represents more than onereference signals. The pattern may also generally represent and/orindicate one or more empty signals and/or one or more data signals(respectively associated resource elements and/or subcarriers). For eachcomb or comb structure with a width of N, there may be N or f(N)different available individual combs. For example, for N=2, there may betwo combs shifted in frequency space by one, or an odd number, ofsubcarriers (e.g., based on a frequency domain offset, or a subcarrieroffset). A comb structure or comb of width of N may be indicated asN-comb. Specific combs of this width may be numbered within N. Forexample, for a 2-comb, there may be a comb 1 (or C1) and a comb 2 (orC2), which may be shifted relative to each other, e.g. to dovetail suchthat all subcarrier covered by both combs carry signaling (associated toC1 and C2 alternatingly in frequency domain).

A comb may comprise two or more, for example at least three or at leastfour, repetitions of the pattern. The comb may indicate a referenceand/or indication, e.g. a resource element and/or subcarrier, which maybe related to the upper and/or lower boundary in frequency, regardingthe arrangement and/or location in frequency of a first pattern, and/orthe relative shift of the pattern and/or comb in frequency. Generally, acomb structure may cover at least part, and/or at least the majority,and/or essentially all or all resource elements and/or subcarriers ofthe plurality of resource elements and/or subcarriers, and/or thesymbol.

A comb structure may result from combining two comb structures, whichmay in particular comb structures with pattern comprising only onereference signal. A comb structure may be determined and/or amendedbefore transmission, e.g. based on other reference signaling to betransmitted, e.g. on a different antenna port. In this context,reference signals may be replaced by empty signals to avoid overlapand/or interference. Generally, if the other reference signalingutilises a comb structure as well, a different/new comb (as acombination of combs) may be considered to be determined, e.g. with lessdense reference signal distribution and/or a different/wider pattern.Alternatively, or additionally, combs may be combined to increase thereference signal density, e.g. by combining combs with different widths,and/or with shifted offsets.

Generally, a comb structure may represent and/or comprise and/or becomprised of any of the combs/comb structures described herein.

In general, a clear channel assessment (CCA) procedure may comprisemonitoring and/or performing measurements on a frequency range and/orchannel and/or carrier and/or spectrum; in some cases a CCA proceduremay also be referred to as LBT procedure; e.g., if only one CCA isperformed for a LBT procedure. In particular, the CCA procedure maycomprise determining whether a channel or frequency range or spectrum orcarrier is occupied, for example based on one or more parameters, e.g.measured or monitored energy and/or power and/or signal strength and/orenergy density and/or power density or similar. A CCA procedure may beperformed and/or pertain to a specific time interval (also referred toas CCA duration), for example a measuring or monitoring interval overwhich measurement and/or monitoring is performed. The CCA procedure maybe performed and/or pertain to a specific frequency range (also referredto as CCA frequency range), for example a measurement and/or monitoringrange. The CCA frequency range may be part of and/or comprise thefrequency range and/or carrier and/or spectrum and/or channel to beaccessed (which may be referred to as access target frequency range, oraccess target in short; accessing in this context may be considered torefer to transmitting signaling on the range and/or carrier and/orspectrum). The CCA frequency range may be considered representative ofthe access target frequency range in terms of occupation status(occupied or non-occupied). A CCA procedure may indicate whether theaccess target is occupied or not, for example by comparing measurementresults with one or more threshold values. For example, if the measuredpower or energy over the CCA duration is lower than an occupancythreshold, the access target may be considered unoccupied; if it reachesor is higher than the threshold, it may be considered occupied. Adetermination as unoccupied may be considered a positive result; adetermination of occupied may be considered a negative result. AListen-Before-Talk procedure (LBT) may comprise one or more CCAprocedure in an LBT time interval, for example with the same durationand/or same condition or threshold for positive result, or withdifferent durations and/or different conditions or thresholds. An LBTprocedure may be considered positive if a threshold number of CCAs ofthe LBT procedure are positive, for example each or half, and/or aminimum consecutive in time are positive. A positive LBT and/or CCAprocedure may allow access to the access target for transmission, forexample to be accessed within an access time interval. Access(permission to transmit) may be valid for a channel occupation time(COT); the maximum time of access may be a maximum COT (M-COT). The timeof access may be referred to as transmission duration (which may be aslong as the M-COT or shorter). A radio node like a wireless device doesnot have to transmit the whole M-COT after successful CCA/LBT. It may beconsidered that part of the M-COT is passed on to another device, whichthen may transmit (using the rest of the M-COT), e.g. upon and/or basedon suitable control signaling; this may be particularly useful in acentralised system. For example, in centralised system, a base stationmay initiate an access, transmit DL signaling to a wireless devicescheduled for UL transmission such that the wireless device transmitswithin the M-COT after the DL transmission has ended, e.g. due tosuitable scheduling information. The device performing successful accessto start transmission at the beginning of a M-COT or COT may beconsidered the device initiating a COT or M-COT. Depending on whetherthere is a gap between transmissions of different device, one or moreCCA procedures (in particular, shorter in total than for initiation) mayhave to be performed by the device taking over transmission. If a LBTprocedure was unsuccessful, a device may be required to backoff (e.g.,not trying to access for a backoff time interval, which may bepredefined or random). Accessing and/or transmitting on an access targetfrequency range may comprise on the whole bandwidth of the frequencyrange, or on part of it, for example interleaved and/or in a contiguouspart and/or utilising frequency hopping, and/or may be based onallocated and/or scheduled and/or configured resources, for example intime domain (e.g., for a number of symbols or a time interval) and/orfrequency domain (e.g., as in terms of frequency subranges and/orsubcarriers and/or PRBs and/or groups of PRBs assigned for transmission,e.g. allocated or scheduled or configured).

A transmission source may in particular comprise, and/or be representedby, and/or associated to, an antenna or group of antenna elements orantenna subarray or antenna array or transmission point or TRP or TP(Transmission Point) or access point. In some cases, a transmissionsource may be represented or representable, and/or correspond to, and/orassociated to, an antenna port or layer of transmission, e.g. formulti-layer transmission. Different transmission sources may inparticular comprise different and/or separately controllable antennaelement/s or (sub-)arrays and/or be associated to different antennaports and/or ports for reference signaling (e.g., such that referencesignaling on different ports is shifted relative to each other, e.g. incode domain and/or cyclic shift and/or frequency domain and/or timedomain, and/or is based and/or represents a different sequence root). Inparticular, analog beamforming may be used, with separate analog controlof the different transmission sources. An antenna port may indicate atransmission source, and/or a one or more transmission parameter, inparticular of reference signaling associated to the antenna port. Inparticular, transmission parameters pertaining to, and/or indicating afrequency domain distribution or mapping (e.g., which comb to use and/orwhich subcarrier or frequency offset to use, or similar) of modulationsymbols of the reference signaling, and/or to which cyclic shift to use(e.g., to shift elements of a modulation symbol sequence, or a rootsequence, or a sequence based on or derived from the root sequence)and/or to which cover code to use (e.g., (e.g., to shift elements of amodulation symbol sequence, or a root sequence, or a sequence based onor derived from the root sequence). In some cases, a transmission sourcemay represent a target for reception, e.g. if it is implemented as a TRPor AP (Access Point).

In the context of this disclosure, there may be distinguished betweendynamically scheduled or aperiodic transmission and/or configuration,and semi-static or semi-persistent or periodic transmission and/orconfiguration. The term “dynamic” or similar terms may generally pertainto configuration/transmission valid and/or scheduled and/or configuredfor (relatively) short timescales and/or a (e.g., predefined and/orconfigured and/or limited and/or definite) number of occurrences and/ortransmission timing structures, e.g. one or more transmission timingstructures like slots or slot aggregations, and/or for one or more(e.g., specific number) of transmission/occurrences. Dynamicconfiguration may be based on low-level signaling, e.g. controlsignaling on the physical layer and/or MAC layer, in particular in theform of DCI or SCI. Periodic/semi-static may pertain to longertimescales, e.g. several slots and/or more than one frame, and/or anon-defined number of occurrences, e.g., until a dynamic configurationcontradicts, or until a new periodic configuration arrives. A periodicor semi-static configuration may be based on, and/or be configured with,higher-layer signaling, in particular RCL layer signaling and/or RRCsignaling and/or MAC signaling.

In this disclosure, for purposes of explanation and not limitation,specific details are set forth (such as particular network functions,processes and signaling steps) in order to provide a thoroughunderstanding of the technique presented herein. It will be apparent toone skilled in the art that the present concepts and aspects may bepracticed in other variants and variants that depart from these specificdetails.

For example, the concepts and variants are partially described in thecontext of Long Term Evolution (LTE) or LTE-Advanced (LTE-A) or NewRadio mobile or wireless communications technologies; however, this doesnot rule out the use of the present concepts and aspects in connectionwith additional or alternative mobile communication technologies such asthe Global System for Mobile Communications (GSM) or IEEE standards asIEEE 802.11ad or IEEE 802.11 ay. While described variants may pertain tocertain Technical Specifications (TSs) of the Third GenerationPartnership Project (3GPP), it will be appreciated that the presentapproaches, concepts, and aspects could also be realized in connectionwith different Performance Management (PM) specifications.

Moreover, those skilled in the art will appreciate that the services,functions and steps explained herein may be implemented using softwarefunctioning in conjunction with a programmed microprocessor, or using anApplication Specific Integrated Circuit (ASIC), a Digital SignalProcessor (DSP), a Field Programmable Gate Array (FPGA) or generalpurpose computer. It will also be appreciated that while the variantsdescribed herein are elucidated in the context of methods and devices,the concepts and aspects presented herein may also be embodied in aprogram product as well as in a system comprising control circuitry,e.g. a computer processor and a memory coupled to the processor, whereinthe memory is encoded with one or more programs or program products thatexecute the services, functions and steps disclosed herein.

It is believed that the advantages of the aspects and variants presentedherein will be fully understood from the foregoing description, and itwill be apparent that various changes may be made in the form,constructions and arrangement of the exemplary aspects thereof withoutdeparting from the scope of the concepts and aspects described herein orwithout sacrificing all of its advantageous effects. The aspectspresented herein can be varied in many ways.

Some useful abbreviations comprise

Abbreviation Explanation ACK/NACK Acknowledgment/NegativeAcknowledgement ARQ Automatic Repeat reQuest BER Bit Error Rate BLERBlock Error Rate BPSK Binary Phase Shift Keying BWP Bandwidth Part CAZACConstant Amplitude Zero Cross Correlation CB Code Block CBG Code BlockGroup CDM Code Division Multiplex CM Cubic Metric CORESET ControlResource Set CP Cyclic Prefix CPE Common Phase Error CQI Channel QualityInformation CRC Cyclic Redundancy Check CRS Common reference signal CSIChannel State Information CSI-RS Channel state information referencesignal/ing CW Codeword, encoded and/or modulated information, e.g. in adata block DAI Downlink Assignment Indicator DCI Downlink ControlInformation DFT Discrete Fourier Transform DFTS-FDM DFT-spread-FDMDM(—)RS Demodulation reference signal(ing) eMBB enhanced MobileBroadBand EPRE Energy Per Resource Element FDD Frequency Division DuplexFDE Frequency Domain Equalisation FDF Frequency Domain Filtering FDMFrequency Division Multiplex FR1 Frequency Range 1, e.g. as specified byNR FR2 Frequency Range 2, e.g. as specified by NR HARQ Hybrid AutomaticRepeat Request IAB Integrated Access and Backhaul ICI Inter CarrierInterference IFFT Inverse Fast Fourier Transform IR Impulse Response ISIInter Symbol Interference MBB Mobile Broadband MCS Modulation and CodingScheme MIMO Multiple-input-multiple-output MRC Maximum-ratio combiningMRT Maximum-ratio transmission MU-MIMO Multiusermultiple-input-multiple-output NR 3GPP New Radio system NR-RS NRReference Signal (any type) OCC Orthogonal Cover Code OFDM/A OrthogonalFrequency Division Multiplex/Multiple Access PAPR Peak to Average PowerRatio PDCCH Physical Downlink Control Channel PDSCH Physical DownlinkShared Channel PN Phase Noise PRACH Physical Random Access CHannel PRBPhysical Resource Block (P)SCCH (Physical) Sidelink Control Channel PSDPower Spectral Density PSS Primary Synchronisation Signal(ing) (P)SSCH(Physical) Sidelink Shared Channel PTRS Phase Tracking RS PUCCH PhysicalUplink Control Channel PUSCH Physical Uplink Shared Channel QAMQuadrature Amplitude Modulation QPSK Quadrature Phase Shift Keying RANRadio Access Network RAT Radio Access Technology RB Resource Block RNTIRadio Network Temporary Identifier RRC Radio Resource Control RSReference Signal RSRP Received Signal Receive Power RSRQ Received SignalReceived Quality RX Receiver, Reception, Reception-related/side SAScheduling Assignment SC-FDE Single Carrier Frequency DomainEqualisation SC-FDM/A Single Carrier Frequency DivisionMultiplex/Multiple Access SCI Sidelink Control Information SINRSignal-to-interference-plus-noise ratio SIR Signal-to-interference ratioSNR Signal-to-noise-ratio SR Scheduling Request SRS Sounding ReferenceSignal(ing) SSS Secondary Synchronisation Signal(ing) SVD Singular-valuedecomposition TB Transport Block TCI Transmission ConfigurationIndicator TDD Time Division Duplex TDM Time Division Multiplex TRPTransmission Point, Transmission/Reception Point TRS Tracking RS TXTransmitter, Transmission, Transmission-related/side UCI Uplink ControlInformation UE User Equipment URLLC Ultra Low Latency High ReliabilityCommunication VL-MIMO Very-large multiple-input-multiple-output ZF ZeroForcing ZP Zero-Power, e.g. muted CSI-RS symbol

Abbreviations may be considered to follow 3G PP usage if applicable.

1. A method of operating a receiving radio node in a wirelesscommunication network, the method comprising: receiving signaling basedon evaluating Phase Tracking Reference Signaling, PTRS, associated tothe signaling, evaluating being based on assuming a power level of PTRSrelative to associated data signaling based on at least one of thenumber or PTRS ports and transmission sources for the signalingindicated to the receiving radio node.
 2. A receiving radio node for awireless communication network, the receiving radio node configured to:receive signaling based on evaluating Phase Tracking ReferenceSignaling, PTRS, associated to the signaling, evaluating being based onassuming a power level of PTRS relative to associated data signalingbased on at least one of the number or PTRS ports and transmissionsources for the signaling indicated to the receiving radio node.
 3. Amethod of operating a transmitting radio node in a wirelesscommunication network, the method comprising: transmitting signalingcomprising Phase Tracking Reference Signaling, PTRS, the relative powerlevel of the PTRS to associated data signaling of the signaling beingbased on at least one of the number of PTRS ports and transmissionsources used for transmitting the signaling.
 4. A transmitting radionode for a wireless communication network, the transmitting radio nodebeing configured to: transmit signaling comprising Phase TrackingReference Signaling, PTRS, the relative power level of the PTRS toassociated data signaling of the signaling being based on at least oneof the number of PTRS ports and transmission sources used fortransmitting the signaling.
 5. The method according to claim 1, whereinsignaling comprises first signaling and second signaling.
 6. The methodaccording to claim 1, wherein the relative power level corresponds to atransmission power level.
 7. The method according to claim 1, whereinthe signaling comprises first signaling and second signaling, whereinthe first signaling comprises first Phase Tracking Reference Signaling,PT-RS, on a first set of subcarriers, and the second signaling comprisessecond PT-RS on a second set of subcarriers, wherein the first set ofsubcarriers is non-overlapping with the second set of subcarriers. 8.The method according to claim 1, wherein at least one of: firstsignaling of the signaling is muted on a second set of subcarriersassociated to second PTRS of second signaling of the signaling; andsecond signaling of the signaling is muted on a first set of subcarriersassociated to first PTRS of first signaling of the signaling.
 9. Themethod according to claim 1, wherein the relative power level isdependent on one or more Modulation and Coding Schemes associated to thesignaling.
 10. The method according to claim 1, wherein the relativepower level is in conformance with a table.
 11. The method according toclaim 1, wherein the relative power level is indicated by Energy PerResource Element, EPRE.
 12. A computer storage medium storing a computerprogram comprising instructions causing processing circuitry to at leastone of control and perform a method of operating a receiving radio nodein a wireless communication network, the method comprising: receivingsignaling based on evaluating Phase Tracking Reference Signaling, PTRS,associated to the signaling, evaluating being based on assuming a powerlevel of PTRS relative to associated data signaling based on at leastone of the number or PTRS ports and transmission sources for thesignaling indicated to the receiving radio node.
 13. (canceled)
 14. Thereceiving radio node according to claim 2, wherein signaling comprisesfirst signaling and second signaling.
 15. The method according to claim3, wherein signaling comprises first signaling and second signaling. 16.The method according to claim 3, wherein the relative power levelcorresponds to a transmission power level.
 17. The method according toclaim 3, wherein the signaling comprises first signaling and secondsignaling, wherein the first signaling comprises first Phase TrackingReference Signaling, PT-RS, on a first set of subcarriers, and thesecond signaling comprises second PT-RS on a second set of subcarriers,wherein the first set of subcarriers is non-overlapping with the secondset of subcarriers.
 18. The method according to claim 3, wherein atleast one of: first signaling of the signaling is muted on a second setof subcarriers associated to second PTRS of second signaling of thesignaling; and second signaling of the signaling is muted on a first setof subcarriers associated to first PTRS of first signaling of thesignaling.
 19. The method according to claim 3, wherein the relativepower level is dependent on one or more Modulation and Coding Schemesassociated to the signaling.
 20. The method according to claim 3,wherein the relative power level is in conformance with a table.
 21. Themethod according to claim 3, wherein the relative power level isindicated by Energy Per Resource Element, EPRE.